Crayfish Stats
Minimum Tank Size: 5 Gallons
Care Level: Easy
Water Conditions: PH 6.5-8 and Medium Hard to Very Hard
Temperature: 65-75 F (18-23 C)
Maximum Size: 3 inches (8 centimetres)
Introduction
For anyone looking for a quirky and interesting pet, the freshwater crayfish is an excellent choice.. They are easy to care for, extremely hardy, and often interact with their owners. While crayfish are definitely not safe for a community fish tank, it is well worth having a tank dedicated to crayfish just to enjoy their antics.
When choosing a freshwater crayfish, it’s important to know that there are well over 100 species of crayfish from around the world. While most crayfish require cool water, some require tropical temperatures to thrive. Before purchasing a crayfish, a owner should do some research to determine the crayfish species needs. If a crayfish is well cared for, they will usually live 2-3 years, with some species living even longer.
Housing
A single crayfish can be kept in a relatively small aquarium. A 5 to 10 gallon aquarium is usually more than adequate, especially if regular water changes are provided. Crayfish are notorious for hiding their food, and will often have a stash hidden away in a cave or flower-pot. On top of that, they are also messy eaters, and when coupled with hidden food , water quality can quickly decline. When doing water changes, you should always check for a stash of food in any of the crayfish hiding spots.
If more than one crayfish is going to be housed in a tank, then a minimum of 20 gallons need to be provided. Crayfish are cannibalistic by nature, and when a crayfish moults it is nearly defenseless until its shell hardens again. During this time, it will hide for a few days, so don’t be too alarmed if a crayfish disappears for a up to a week at a time. Because of this, it is very important to provide numerous hiding places and enough space for each crayfish in the aquarium – unless someone wants their crayfish to become an expensive meal for the other tank inhabitants.
It becomes much trickier when it comes to housing crayfish with fish. There are many accounts of people successfully keeping crayfish and fish together, but given enough time, either the fish or the crayfish is going to be eaten. There is nothing worse than losing a large, expensive fish to a crayfish over the course of a night. Or alternatively, finding crayfish parts scattered across an aquarium, with a very full looking fish. While a person can certainly try to keep fish and crayfish together, it ends badly more often than not.
The filtration for a crayfish should usually be a HOB (Hang-on-back) filter. While a sponge filter is cheaper than an HOB filter, the air line leading out of the tank gives the crayfish a perfect escape route. If you leave the crayfish alone long enough, you will eventually see a crayfish running around on the floor of your fish room.
Feeding
A crayfish’s main diet should be comprised of sinking Shrimp Pellets, but they also enjoy some green vegetables and frozen foods in their diet. They are not picky when it comes to green vegetables and can be offered cabbage leafs, zucchini medallions and shelled peas. As for frozen foods, they happily accept small portions of frozen fish, daphnia, bloods worms and brine shrimp.
A word of warning – crayfish love aquatic plants and will eat any that are put in the tank with them. An adult crayfish can strip a heavily planted aquarium bare in a matter of days. So while it may be a good place to dispose of unwanted plant clippings, you should never put any plants in their aquarium that aren’t replaceable.
Breeding
Most species of crayfish will breed at any time in the home aquarium, though feeding high quality foods and keeping the water pristine will help trigger breeding behavior. Crayfish can be frustratingly hard to sex for someone new to keeping them, but the easiest way is to look at the swimmerets. The males will have swimmerets that extend past the back legs, while the females won’t have any past the back legs.
When mating begins, the male deposits a sack of sperm on the female who then passes her eggs through the sperm to fertilize them. After the eggs have been fertilized, they are then kept under the tail by the female who should be placed in a tank on her own at this point.
After around four weeks, the eggs will hatch and the young crayfish will emerge. The female crayfish will take care of the young for a short period of time, but should be removed after a few days to prevent the fry from being eaten. A large nursery tank is required if any number of crayfish fry are expected to survive as they are extremely cannibalistic like their parents.
The baby crayfish can be feed blanched cabbage leafs or lettuce leaves, and also consume detritus in the tank. As the crayfish grow, the larger ones should be removed from the tank as they will feed voraciously on the smaller crayfish.
Eliz says
I found my crayfish and if the breed I have a 50. Gallon tank so I can’t get them out
Robert Brand says
That’s a great tank for them. The hatchlings should be fine with such a large tank, even with the parents still in there. You’ll lost some, but if you provide enough hiding places you should be good to go.
Chloe says
So I found a crayfish and I have a small 2 and a half gallon tank is that ok
Robert Brand says
It’s on the low side, but if you add a sponge filter to the tank, it should alright – assuming the crayfish is small. A big one is probably too large to live in there comfortably.
Mee says
You should have atleast a 30G tank.
Nikki says
My crayfish at eight but after few weeks I see no babies no more eggs so what went wrong
Robert Brand says
Was there a male in the tank as well? It’s like the eggs weren’t viable to begin with, but if they were fertilized the most likely problem is fungus. Did you see any sort of growth on the eggs?
aidan says
i have a native aquarium that is 30 gallons. i have a female crayfish. if i put a male in, will they just mate?
Chris Graham says
@eliz the easiest way to catch a crayfish in an aquarium is to use a square container with a tightly matching lid, put the container on one side of the crayfish and the lid on the other side with a few inches to spare in both directions, use the lid to coax the crayfish towards the container, this week I got my first bunch of crayfish and using that method it takes me less than a minute to get each one out of the tank when needed with little to no stress on them 😀 mine are the blue variety I call them my alien army
Tiff6371 says
OR……use a fishnet……just saying
Chris Graham says
they tend to grab on to the net and not let go or swim away rather fast so the net is far more stressfull on them plus on average takes 10 times longer to catch them, container method takes a minute so by far would be the best method..
Tiff71 says
I respect your opinion but disagree. My Blue female and Phantom male hate to be granted by their saddle. The struggle and flick their tails and contort to try to use their pincers. When I net them they don’t struggle at all. Takes me about 3 minutes tops, plus I use a large net with very small holes. Though mine are very spoiled and I handle them quite often. So that may be why mine don’t seem to mind the net 🙂
Chris Graham says
not sure what you mean by granted them by thier saddle, did you mean grabbed? I never once stated that I grabbed mine if thats the case, I stated I coax them into the container using a lid, they go into it on their own not by force when they go into the container I just shut the lid down and pull them out….
Tiff71 says
Yes I know you did not state that you grabbed yours by their saddle. I’m simply stating what mine do not like. They hate to be picked up by their saddle, and tend to not mind if I use a large net with small holes.
someone says
just use your hands they don’t hurt that bad. if you crab their shell behind there pinchers they can’t get you.
Ethan cabanaw says
hi am i doing something wrong my female and male crayfish have mated over 1 month ago and still have not seen any baby eggs on her under side can someone tell me why please
Robert Brand says
It’s hard to say what went wrong. It could be that something went wrong with the eggs, it could be they weren’t fertilized property, or maybe even something. Just try to be patient and they should try again.
Reina says
Hey there sorry to comment on this but can’t seem to find out where to post my own comment:( but I recently got an orange crayfish and it molted the next day. Also I wasn’t aware that they eat there exoskeleton so I took it out is that bad? Also I have some lil fish in my tank with him and he is very clever he goes into the plant and catches the fish. I feed him alage wafers but he doesn’t seem to be eating them? I feel like he’s only getting his food from the fish? Also he’s in a 5 gallon by himself with 4 lil fish but im putting him in a 20 gallon because I want to purchase 3 more cryfish. Do I let the 20 gal tank cycle for a few days or can I just ad the drops I got from the pet store to speed it up? Do I do full or half water changes? I have a filter and heater.
byk0010337 says
what is a cryfish?
Gene Oser says
Okay, So I have had craw-fish my whole life, This is the first time I have had them breed and the mom die’s while the eggs are still under her un-hatched. Is there a way to go about keeping them alive? I removed the mom from the tank I used a spoon and gently removed her eggs and put them in a separate Tupperware dish, Is there any other advice you could give me ?
Robert Brand says
Sorry for the delay in getting back to you. The only way that you could possible keep them alive is by using an anti-fungal, but I’ve never known anyone to keep eggs alive after the parent has passed away. That’s not to say that it can’t be done, but beyond trying to keep fungus off of the eggs, I’m not sure what else could be done.
Donald says
If u put them in tall glass with a light air bubble streem in a tank with some quick cure they might hatch
Kan viroat says
Hi do you have any document or video for hatching crayfish by machine??
Thanks
Robert Brand says
Sorry, but I don’t have anything like that. Are you looking to start farming them?
Robert Brand says
Also, just as another note, they should be kept in a full aquarium if at all possible. If they hatch in the tupperware, the water quality would quickly crash, and it would be very difficult to feed them in there.
Margot McDermott says
There is a good you tube video on keeping shrimp eggs alive after death of mom. Essentially you keep a bubbler on them, and add antifungal that is safe for inverts. Also keep the temp slightly warm – just search you tube.
bradley says
I have a fresh water lobster in my tank and for the first time he seems to be stiff and not moving and basically laying on his side.iv never seen this behaviour before and wondered what its from . If hes dying or ready to shed his skin. My other 2 lobsters are still healthy and active
Robert Brand says
How long has it been laying on its side? During moulting, they may lie on their side for short periods of time while they shed. If it’s been more than a short while, then it sounds like it might be illness. I would consider checking your water parameters. Also, is your crayfish getting any iodine in its diet? Shrimp pellets and algae wafers are generally good sources of iodine which are very important for crayfish.
bradley says
i feed them nutrafin max bottom feeder pellets and a piece of hake every few days, He has been on his side for about 20 min , i will check the water parameters as you said to evaluate the next step
Emma says
I was just wandering if all crayfish sexing is the same. I have 3 freshwater crayfish at home and have no idea how to tell because if it is all the same are males more rare than femles?
Robert Brand says
As far as I know, all of the popular species of crayfish are sexed in the same way (though with the sheer number of species out there, I could be wrong). But the easiest way to tell is to look for the claspers on the male. I found this picture which makes it easy to see the difference.
Zoe says
The blue Crayfish male will have red strips on his claws but not straight away
Zoe says
Also my female blue has been carrying eggs for almost 3 mths opposed to the 4 weeks suggested above. One just hatched today.
Robert Brand says
Water temperature can effect how long it takes the eggs to hatch, although most species eggs hatch with three to six weeks. The fours weeks is just an average, and because this article covers dozens, and perhaps even hundreds of species kept in aquariums, it was difficult to be more precise.
Emma says
Ok thankyou because i just had no idea for about the last two years!!
Tavia says
I have a blue crayfish that seems to have babies attached to her. I have her in a 10 gallon tank with 4 small tropical fish. How do I help them survive? do I put in a tank divider? Do I need t separate her from the hatchings?
Robert Brand says
A divided would work for now, and leave the hatchlings on her until they let go on their own. Once they let go of the mother, the mother can be removed. The problems come later when the crayfish hatchlings start to mature. They are very cannibalistic, and you will have very high mortality if they are kept together. Most people who try to breed crayfish have numerous tanks to split up the hatchlings.
vanessa says
Ok we just got our first crayfish and we are a little concerned with the tank. It is a 3 gallon tank with a huge rock. No lid on the top but water is not even half way up the tank. Any help would be great
Robert Brand says
Sorry about the delay in getting back to you, but that tank should be fine as long as you keep on your cleaning schedule. Also make sure that your crayfish isn’t hording food, or that will quickly foul your water. I would recommended getting a lid if you can though, so you can fill the tank with more water.
Rap1911 says
Girlfriend, them things are master escape artists! If your tank is uncovered, expect to find it up under your couch, or on the floor hiding in a corner of the house! #WatchYourStep
Rap1911 says
This article is such a lie! I bought a white freshwater crayfish or Lobster from PetCo. Within days it began catching and eating 6 of my tiger barbs, all of my Red Minor Serpae Tetra, 7 of my Colombian Tetras, and 6 of my Brazilian Tetra. I plan on catching it this afternoon and getting permanently rid of it so I can restock my 75 gallon tank! I feel so lied too. Everything I read online about them said they were peaceful and DID NOT eat healthy, big fish, that were too fast for it to catch. I guess my small lobster is different. Maybe I should have named him Speedy Gonzales or Predator instead of Snow. DO NOT buy this as a pet unless you just have catfish in your tank. It never bothers those.
Robert Brand says
How is this article a lie? This is a quote from the article, “but given enough time, either the fish or the crayfish is going to be eaten. There is nothing worse than losing a large, expensive fish to a crayfish over the course of a night. While a person can certainly try to keep fish and crayfish together, it ends badly more often than not.” I’d say you were sufficiently warned.
Lauren says
I AM PRETTY SURE YOU SAID THEY WILL EAT EXPENSIVE FISH
Heather Taylor says
Oh my God I can’t believe that you’re arguing with somebody who gave you the correct information and you should have done much more research in the first place.
I’m so sick of the younger generation that can’t take responsibility for itself
LP says
I am having the opposite problem. I put about 10 feeder guppies in with my vanilla lobster and it won’t eat them. As a result, the fish are eating all of his food. Should I remove the fish? Am worried about him not getting enough food.
Robert Brand says
If you like keeping the fish in there, then I would keep them in there. There are strategies to deal with feeding a crayfish with other hungry fish in the tank. The best way to do it is to feed the crayfish after the lights go out. It will usually find the food then, and the guppies will normally be inactive.
Another way to do it is to feed them at the same time on different sides of the tanks. Put food on both sides, so while the guppies eat on one side, the crayfish will be able to eat on the other side.
And placing vegetables in the tank will also help, as guppies will barely be able to put a dent in the vegetables, and the crayfish will likely be able to eat its fill. Make sure to remove any leftover vegetables after 24 hours, so you don’t foul the water. Also, check caves and decorations during water changes, since crayfish are known to hide the food.
Percelious says
How long does it take to breed crawfish
Robert Brand says
Do you mean how long until they breed after being added? Some crayfish need triggers to breed, while others breed year round. If you’re having trouble getting them to breed, you should reduce the temperature and lighting for a few weeks, and then over the course of another few weeks, slowly increase the temperature and light. This simulates spring, and will often trigger breeding in them.
Mindy says
I think they all have different personalities, and food preferences, similar to humans. Some of us are peaceful vegetarians, some are peaceful carnivores, etc. Why did you leave the crayfish in long enough to eat so many fish?
mark sagusti says
we have a blue crayfish and the egg are all black but dose not seem to be growing. its been 4 days and how long dose it take to hatch ?
Robert Brand says
Sorry about the delay in getting back to you, but eggs take a minimum of four weeks to hatch. And that’s only for warm water species. Cold water crayfish can have eggs on them for as long as six weeks. Hope this helps.
Kevin says
I was considering getting an orange dwarf crayfish for my. 10g. Most websites I have read say that they are fairly peaceful and can be kept in a community tank,. I have read some reports of them eating fish though. What should I think?
Thanks
Robert Brand says
I actually did an article on dwarf crayfish recently. You can check it out here.
But in my experience, they are the only crayfish that can generally be kept safely in a community tank. With that being said, there is always some danger in keeping crayfish with fish. They will eat anything that they can, and if a fish is sick, or they just get an opportunity, they will try to eat the fish. This is much more rare with dwarf crayfish, but it is still known to happen in rare instances. So always proceed with caution.
Also, you will still have to provide hiding places for the crayfish during molting, as fish will be more than happy to eat a small, vulnerable crayfish.
Anonymus says
@ Kevin….
I’ve had the same problem but with my Red Crystal shrimps and I managed to hatch the eggs with no problem.
What you can do after you collect the eggs:
– put them in a fish net(the one used to catch the fish in your aquarium) and put in in front of the output spray bar if you have a canister filter
-put them in a breeding net and place the net under the output of your HOB filter.
I had a canister filter and I used a fish net in front of the output spray bar to keep the eggs moving and aerated
Good luck.
Venessa says
i just recently got a crayfish and bought shrimp pellets and was wondering how often should we feed him every website states what you should feed them but not how much
Robert Brand says
Usually one or two small pellets is more than enough. I’ve read some estimates that they only need to eat about 5% of their body weight a day, so try to judge the amount of food based on that. Also, always check their cave during weekly cleanings, since they are known to horde food, and it can accumulate in their and foul the water.
Kimberly says
I just got an Australian Blue Lobster and I was wondering if I needed to put in some sort of bubble making machine? And how much I could fill my 10g tank upto?
Robert Brand says
You don’t necessarily need a bubbler, but you should have some type of filter on the tank. I tend to use sponge filters, but just make sure that they can’t climb up the air line going into the tank. Also, you can filter the tank to within about two inches of the top with no problem. Just make sure that you give the crayfish a chance to acclimatize to the new environment, if it’s not currently fully submerged in water. This can be done by creating an environment where he can submerge or stay above the water if it chooses to at first.
Kimberly says
And I was also wondering if I could take my lobster out of the tank and for how long
Robert Brand says
It’s best not to take it out unless you have to. You can cause problems for it if air bubbles become trapped in the gills. You’ll need to re-acclimatize it to water again, by placing it in a bucket where the water isn’t over its head for a least 24 hours, and then hold it upside in the tank to get rid of the last bubbles.
Tyler says
Wondering how often crayfish can have babies.
Robert Brand says
It all depends on the species. Cold water crayfish tend to only mate when they believe it is spring, while the tropical variants will usually mate every few months.
Mark says
I keep crayfish together with fish and they breed regularly. The orange ones, I find are the most passive. The blue and white ones sometimes have a go at each other but will usually only take a pincer off. They very rarely catch a fish, even at night, because they are relatively slow moving. If a fish is sick they will eat it. But healthy fish are usually safe.
Robert Brand says
The dwarf crayfish I find are quite good with fish, and I’ve had limited success with electric blue crayfish. But I’ve also seen some that terrorize the tank. The only ones that I’ve never had any luck with are the red North American varieties. The few times I’ve risked keeping them with fish, it’s been nothing short of a chain saw massacre the minute the lights went out at night.
Mark says
My larger fish even share wooden barrel hiding places tgether with crayfish and I havent lost one yet. Crayfish can also be trained to take the pellet from your fingers if you have enough patience and it impresses guests no end
Robert Brand says
That sounds really cool. I have some fish that can do that, but I’ve never tried that with crayfish. Was it with electric blue crayfish? I may have to try that in the near future.
kansascutiemom says
I posted a response to this elsewhere, but this is the thread I was searching for. Hand-feeding is indeed possible! I have three freshwater crayfish and they are amazing little critters. It took me about two weeks (maybe even a little less) to get them used to the idea, but now as soon as I put my hand in the water at feeding time, they come right out. They hold their pincers up (in a more “polite” fashion now instead of defense mode) and gently take their pellets right from my fingers. It makes me feel pretty darn awesome that they now trust me enough to let me feed them. I highly recommend crayfish for any aquarium owner… They have quickly become my favorite “water-pet!”
Robert Brand says
That’s really amazing that you were able to do that. I always consider it a win when I can finally make my crayfish comfortable enough that they don’t hide all day. But they are one of the most interesting aquarium pets to keep, and I would recommend them to almost anyone.
Israel says
Mine,, I just tap the aquarium top a few time before feeding them and they come out from there hiding spot and go all to the same corner of the tank where I always feed them,,,
That’s amazing!!!!
Ryan says
How can I get my blue dwarf crawfish more blue??
Robert Brand says
One of the best ways to improve a crayfish’s colour is through lighting. Assuming that you are feeding it a high quality food (spirulina, sinking pellets and vegetables), and keeping the water as clean as possible, you should add a fluorescent light to the tank. Many crayfish will become dull under an incandescent light, but a fluorescent light that mimics natural light can improve their colouring considerably.
Rasmus Christensen says
Hey. we just got ourselves a red clarkii crayfish and it is really a fun and cool animal. We were wondering if it would make any sense to feed it with living bait, maybe a scrimp or clam?
Robert Brand says
They definitely appreciate live food in their diet, and ghost shrimp are a good, cheap option to feed them. With that being said, depending on the size of the crayfish and the tank, they may have trouble catching the shrimp. As for the clam, I don’t know if they’d be able to eat it. But even if they do find a way to get at it, most clams would be too large to fully eat, and the leftovers would really foul the water. I would stick to live food, and maybe even try other aquarium staples like blackworms that are easy to obtain and feed.
Rasmus Christensen says
Thanks a lot Robert. We have a 7 gallon tank, and it is about 8 cm long. It is pretty active and fast, but so are the shrimp I gues. I gues that we could try and bring a ghost shrimp home, and take it up again if it isn’t a succes.
Thanks for this awesome website and forum. We have learned a lot from it.
Amalraj says
i need some few cool collection of crayfish.. where can i get ? can anyone sell some to me ?
Robert Brand says
Some good places to find crayfish are aquabid.com if you’re in the United States, or on local forums. Many local forums have a section where people trade and sell fish. I have purchased many on my more rare fish on my local forum. Also, many of the larger chains can custom order crayfish for you. This are usually limited to some of the more popular and common types, so I don’t know if this is what you would be looking for.
Morgan says
My white crayfish just had her babies last night i counted at least 15 i can’t possibly keep them all al though i have a 55gal tank she is housed with cichlids and the babies would surely be eaten if i kept them all have you Had good experiences with aquabids cause i heard on other sites it was a place to sell but with no reviews
Robert Brand says
I’ve never actually tried aquabid, since I’m in Canada and very little of it ships to this country. With that being said, the people I know who have used it, have been pretty happy with it. Another option is Kijiji which is quite popular here for that sort of thing, and the thing that I find the best is local fish forums. Most major cities will have a forum focused on the area, and you can usually find really great people through the forum.
If you decide to go with aquabid, I hope that you have good luck with it
Vihanga From Sri Lanka says
hi i took a new lobster male and female and they are very rare pink color i would like to breed them and i will read your instructions and i comment this because this is very useful for children and others like us i am 14 years old and thank u again and again
Robert Brand says
Good luck breeding your crayfish. I hope your successful. I’d love to see some more pink crayfish on the market.
Zak G says
I have a red dwarf crayfish in a ten gallon with 6 guppy tank mates and i was wondering if i should buy him a protective one opening cave? If i do have to buy her this can you direct me to a good cheap (-$10.00) cave o a website! Thank you!
Robert Brand says
It’s always a good idea to provide a crayfish a cave, though I do believe that your crayfish would be safe from guppies. Of course I can’t say that with 100% certainty (and the guppies would probably turn into piranhas if I did), but I can’t imagine guppies threatening a crayfish even during a moult. And if you want to save money on a cave, you can always do it yourself. What I often do is bury a plain clay pot in the subsrate on it’s side. This creates a very affordable cave, and it will grow a thin layer of algae on it to give it that natural look. If you don’t like that, you can collect some flat stones from a local stream, allow them to dry out fully, and then clean them thoroughly. Once you’re sure that they are 100% clean, you can glue them together with aquarium sealant and create your own cave. Both of these ideas will cost under 5 dollars.
Zak G says
What fish go well with a crayfish (he killed all guppies and the tetra(neon) and the ale guppy survived but if ii start over what fish would go well with him in my 10 gallon
Robert Brand says
If you have a crayfish that regularly hunts fish, you really won’t find any fish that will go well with it. I’ve experimented on my own, and I haven’t found anything that can survive with an aggressive crayfish. I have heard that barbs can survive with them, but I’ve never tested that. I’ve even known people who’ve tried going with larger fish, and come home to a crayfish eating an arowana. Plus with larger fish, if the crayfish doesn’t get them, you can almost be sure that the fish will eventually get the crayfish.
Beth says
I have Danio fish and Clown loaches with my Electric Blue Crawfish- and they do fine.He also was making my Neons part of his diet- so I moved them to another tank. He does alright with the other two varieties- I was told because they are faster moving. Hope that helps! Beth
artwritewonder says
A crayfish will kill anything you put in with it. We <3 our red, but she Does Not Play Well With Others. Fish, snails, or shrimp in there with her would be like putting a lizard in a closed cage with our cat. If you don't care about the lizard, okay … or, as long as the lizard can adequately hide, okay … All fish are bait to a crayfish. We have ours in its own tank, & have another tank with peaceful tankmates (golden mystery snails, tetra & vampire shrimp).
Robert Brand says
I’ve had a very similar experience with my crayfish. Unless you are very lucky and get a very peaceful crayfish, eventually it will catch and eat anything in its tank. A lot of people disagree with me, but I always recommend crayfish only tanks.
Lea Insalaco says
I have 2 large adult crays in my 40 breeder tank and have found that they will ALWAYS hunt fish, but if I supply small feeder minnows or guppies for them to hunt and eat, they leave my larger fish alone. The larger fish are a mix of 4″ danios, lg angelfish and a few large goldfish.
Robert Brand says
I’ve had the same experience, and while they aren’t very good fish hunters, they will stalk them relentless. What you’re doing is a smart idea, and is almost like a dither fish to keep them occupied and way from your larger fish. Just a word of warning – I’ve seen them eat much larger fish than angelfish, so you might still get unlucky someday.
Tonya says
My son bought a crawfish for his 20 gallon aquarium that also contains goldfish. Its been about six months with no problems even during moulting. My question is now she seems to be loaded with eggs. She is a solo crawfish. Will the eggs hatch? She’s been going into hiding last few days.
Robert Brand says
It all depends on the species. There are so many species of crayfish out there, it’s hard to know which species you have. I’ve read that some can store sperm for some time, and others are parthenogenetic, which means they can reproduce without fertilization. If you have one of those species, then the eggs may be viable.
What is far more likely though, is that the crayfish is producing non-viable eggs. This is fairly common, and the eggs will likely be abandoned fairly quickly, and you won’t see any crayfish hatchlings.
Edward Clark says
I am considering getting a pair of electric blue crawfish for my community 150G. could I keep another pair/color in the same tank. I never overpopulate with fish, have 2 magnum 350 filters and undergravel with 4 (model 5) pumps. If just the one pair would let some of the offspring survive, I would prefer that. Thank you so much for your input, I just found the site and I am fascinated so far. Edward
Robert Brand says
It’s hard to give advice on crayfish, since they are all so different from each other. What I can say is that more people have success keeping electric blue crayfish with fish than many of the other species. But I will say upfront that anytime you keep crayfish and fish together you’re taking a risk. Eventually, the crayfish will start to pick off fish, or the fish will get the crayfish during a molting.
The key to crayfish survival is giving them numerous caves and hiding places. The more places that they have to hide, the better their chances of not being cannibalized by other crayfish or eaten by the fish during molting. So if you’re will to risk your fish, then you should do well with even two pairs of crayfish in a tank that large. But if you’re not willing to risk your fish, then I wouldn’t do it. And don’t assume size alone will protect your fish – I personally knew someone who lost an adult arowana to a crayfish.
Brandi says
Hello Robert I have a blue lobster and he likes to climb the decorative plants and water filter to try to get to the top of the water almost looks like he is trying to escape, is the behavior normal?
Robert Brand says
It’s completely normal. All crayfish are born escape artists, and they will constantly try to find a way out. Before I started carefully covering my crayfish tank, I used to come home to crayfish running around in my basement. Just make sure that he can’t escape, and he should be fine.
shane875 says
Hey guys! I was wondering if anyone knew if it would be safe the have 1 crayfish and maybe 2 small creek chubs together in a 10g tank? Thanks.
Robert Brand says
Creek chubs are a surprisingly tough fish, but you still take a risk when you put fish and crayfish together. Eventually, either the crayfish, or the fish will likely get injured or eaten. Though in some cases, you can get lucky and keep them together in a well set up aquarium.
You should also know that creek chubs get really large. An average creek chub can grow up to 12 inches in length, and will soon need a much larger tank than 10 gallons. For adult creek chubs you need something along the lines of 55 gallons at the bare minimum.
On a side note, it’s great to see someone keeping North American native fish. I had a tank set up for years with native fish (brown bullhead catfish and pumpkin sunfish), and they’re really underrated fish. I find them a lot more interesting than most of the tropical fish out there.
francisco says
will blue lobster and red claw lobster compatible?
Robert Brand says
I’ve never kept them together myself, but from what I read most species of crayfish will tolerate other species in their tank. I would make sure to have a large tank, with plenty of hiding places for them. Otherwise, you’ll like see some cannibalism in the near future. I would recommend at least 29 gallons, though larger would be better.
Bdub says
How long do they mate for.
I have to crayfish that have been clutched together for over two hours now.
Robert Brand says
In my experience, it tends to last about half an hour. What’s that saying – if mating lasts more than 4 hours contact a doctor?
But all kidding aside, if they mate for too long you should try to separate them. Sometimes the mating goes wrong, and the male gets increasingly frustrated and may kill the female. Though hopefully by now, things will have worked themselves out in your aquarium.
Nani says
I have a little crawfish and shes been laying on her back for about a week. At first I figured she was molting, but after a few days and no progress Im a little worried. She will flip herself right side up, crawl around for awile and then flip back over. Last night she was zooming around and then all the sudden just flipped onto her back. Today I offered some food and she chowed down, but now shes on her back again. Any ideas?
Robert Brand says
The general consensus is that this is caused by iodine deficiency. I would immediately pick up a marine iodine supplement, and begin to add it to your crayfish tank. Though you probably won’t see much improvement until your crayfish’s next molt.
Jessica says
My blue crayfish had babies about a week ago. A good majority of them are still hanging out under her tail, but there are a bunch that have left her and are moving freely about the tank. She seems to be very protective of them, and she doesn’t appear to have any interest in eating them….yet. Should I be moving her away from the babies now? I’ve planted a few lettuce leaves around the tank and drop some small sinking granules in every day for the babies to eat.
Robert Brand says
I would remove the parent as soon as possible. You should also be aware that the fry are cannibals as well, so unless you have a very large aquarium for them, you’re going to lose a lot. It sometimes helps to subdivide the fry into separate tanks based on size. That reduces the cannibalism a fair bit.
ryannurtanio says
I have a red swamp crayfish,i heard that we have to find the ideal temperatures,but the problem is my aquarium is warmer,how to cool it down? Also,how to clean a sand gravel? I cant tell where’s the poo because i have a black sand.can someone help me?
Robert Brand says
There are three main ways to cool down an aquarium. The first is relocating it to a cooler part of the house. The second is to limit the amount of sunlight that the room and aquarium receive. If neither of those would work, then you can set up a fan to blow across the surface of the aquarium. This will help to dissipate some heat.
As for the sand, just hover the gravel hose a few centimeters above the surface, and it will pick up the waste without the sand. You may need to experiment a little bit, but the waste will always be lighter than the sand.
Ben says
Hi Robert, We heve a orange crayfish and the eggs are all black but shes not eeting ?
Robert Brand says
There could be several reasons for this. It may be stress, water quality, or nutrition. I would start with checking your water quality, and looking for sources of stress (other crayfish, aggressive fish, etc). If that seems fine, I would try a marine iodine supplement, to see if that helps at all.
nika says
I got two crawfish from the WARF can I put them in my 29 gallon tank with my goldfish,gubbies,black mollies,neonfish
Robert Brand says
I wouldn’t recommend that at all. A slow fish like goldfish would become a quick meal for the crawfish. The mollies and neons may be alright for a while, but you’re still asking for trouble in the long run. I don’t recommend keeping most species of crayfish wish fish. Though some people argue that it can be accomplished, I’ve had nothing but trouble when I’ve tried it in the past. And this is sentiment that is pretty widely shared by other aquarists.
nika says
OK thanks and also I do have my gold fish in my warm water tank is that OK
Robert Brand says
Goldfish really don’t like warm water tanks. They are a cold water fish, and if the temperature is too warm, for too long, they will start to suffer nerve damage, and may die. If at all possible, I would transfer them to a cold water tank as soon as possible.
habib says
i have 5L aquarium..how many juvenile crayfish can be stocked in the aquarium?
Robert Brand says
To be honest with you, a 5 litre aquarium won’t keep any crayfish – even juvenile ones alive very long. I would recommend a minimum of 19 litres at the minimum. And then it would only keep very young hatchlings alive. In my experience, you start to experience massive cannibalism by the time they reach about a centimeter in crowded conditions.
habib says
can u suggest the cheapest aquarium price with 19L?
Robert Brand says
It all depends on what country you are in. However, with that being said, you can often find very cheap, very basic aquariums at any of the major chain stores. Ignore the big kits that cost cost 40-50 dollars. Just buy the most basic aquarium they have (it’s usually hidden away somewhere or in the back), and then just buy a sponge filter with air pump for it. I know in Canada, you can purchase a setup like this for about 25 dollars. The sponge filter is about 15 dollars and the aquarium about 10, and then I use play sand for the substrate and river rocks to create caves. Very cheap, and yet still a great place to keep crayfish.
Scarlett Ivy says
what if the crayfish attack by predator like turtle
Robert Brand says
Some turtles enjoy eating crayfish, but those are mostly larger ones like snappers. Do you have a turtle in mind for keeping them with?
Yulia says
Dear Robert,
My crayfish is being still for the second day now, he moves a little bit and than freezes like dead, also his eyes start to seem blurry. I am scared and I can’t find any advice.
Robert Brand says
It sounds like it’s getting ready to molt. Before a molt, its common for it to really slow down, and it will most likely try and find a hiding place soon. Beyond that, just make sure that your water quality is alright, and continue to try and feed it a high quality food (removing any excess, since they tend to stop eating before a molt).
Yulia says
Dear Robert,
Thank you for the reply!
Water quality is ok.
I didn’t see him moving today at all and his eyes are paler than yesterday, is it bad?
Robert Brand says
It doesn’t sound like an illness. My money is on it becoming ready for a molt. My crayfish would often get cloudy eyes right before a molt. Keep an eye on it though just to be on the safe side.
Yulia says
Dear Robert,
Thank you very much!
I keep an eye on him, but I don’t know what else to do – he doesn’t move at all, his eyes are completely clear now and he’s got something like bubble on his back – I think he might be dead= (((
http://s23.postimg.org/f2zrw75p7/IMG_3547.jpg
I took a picture, could you please tell what you think?
Thank you!
Best Regards,
Yulia
Robert Brand says
I’m sorry to say, but it looks like your crayfish has shuffled off this mortal coil. Once an invertebrate is sick there’s very little that you can do, unlike most species of fish which you can at least treat with medicine. You can tell from the filaments protruding from between the plates.
Rasmus Christensen says
Hey Robert!
I have a red clarkii crayfish and it has molted…. BUT! It is blue now!
Is that a common thing? I cant seem to find info about a red crayfish turning blue on the internet.
The decorations in the tank are all red, and the gravel is black. I dont know if this has anything to do with the color of the crayfish.
I have one shrimp in the tank with it, and nothing else.
I hope you can give me an answer on this topic.
Just to make it clear, I am really psyched about this! It is awesome!
Robert Brand says
I wish that I could help you with this one. I’ve heard of this happening before, but I’ve never found any scholarly information on why it occurs. I remember reading about this happening in a lab recently, but the scientists weren’t sure why it was occurring. It definitely makes the crayfish a lot more desirable though.
Edit: Found the link – http://www.houmatoday.com/article/20100907/ARTICLES/100909585
Bill Mench says
I only saw this site on pintrist today March 3, 2018 but if you are still there I have also had red crayfish turn blue. I heard that if common crayfish like the ones I caught in my local river are more red when the water is colder and more blue when the water is warmer. So it will get bluer after each molt if the water is kept at normal room temperature. At least that has been my experience.
dyston says
Hey just caught a couple crayfish and already they start to breed I got two females what should I feed the females and how many days/weeks/month does it take for the eggs to be hatched
Robert Brand says
Shrimp pellets should make up most of their diet. But you should also add blanched vegetables and frozen fish food too. I find blanched shelled peas, zucchini and romaine lettuce to be my crayfish’s favorites. As for the fish food, I occasionally offer cubes of bloodworms and brine shrimp to mine. If they are breeding, you may also want to consider adding a marine iodine supplement that you can pick up at fish stores.
Just be careful having that many crayfish though, unless you have a huge aquarium. They are notorious for their cannibalism, and you’ll start seeing losses soon if you keep them in close quarters.
dyston says
Hey Robert I found out I got 7 female cold blooded and I don’t know what to feed them can you tell me what I should feed them
Gilbert says
I have 5 red 3 white and 2 blue with the 1 white one having eggs on her back, when she still with the other crayfish, she eat her own egg by pick it up from her back. So i move her to new aquarium, she always climb my pipe and then she fell, will the egg hatch?
Robert Brand says
Crayfish will often eat their eggs if they are stressed. That behavior should trail off now that she’s in her own aquarium. I would expect that the eggs will still hatch, as long as they were fertilized in the first place.
Christy says
That’s good to know…I was almost positive that’s what my electric blue was doing, the first day I moved her to her own private tank. She chilled out quickly. Still waiting on the rest of the eggs to hatch.
Mel says
I separated my female into her own tank last night as he young were being released. I. I last looked at her around 1am and all was still good she was still releasing them but when I checked again at 6:30am the female had de clawed herself and all the young were dead with half still attached to mum. What did I do wrong or why do you think this has happened.
Robert Brand says
I wish that I knew. That’s an extreme reaction, but it might be stress related. So many things can go wrong, it’s hard to pinpoint it. Was the water treated, and how did you introduce it to the tank?
Anna says
Hello! I have a white crawfish, female. She just went through her second molt. Her first one white and her second one blue, Im not sure what this means, some kind of nutritional deficiency? Also, she seemed to have injured her claw. She was holding very wide for a few weeks and now that she’s molted, the injured one is gone. Ive heard of them declawing themselves in certain situations, was this injury or stressed based?
Robert Brand says
Unfortunately I can’t help you out with the reason for the colour change. There are numerous theories out there, but at this time I haven’t found one conclusive one as to why this happens in captivity.
The injury during molting is a far more common problem. While there are numerous possible reasons as to why this may have happened, the most common one is that there is an iodine deficiency in your crayfish. This can be easily rectified by picking up a marine iodine supplement (use at maybe 50% or less recommended dosage amount)at your local fish store, and your crayfish should hopefully recover from its injury during its next molt.
Mattew Selle says
I can’t find a plase to get crafish food were shood I get it?
Robert Brand says
It depends what country you’re in you. In most countries you can order it online. And if it really becomes a problem, just make your own fish food and use it for crayfish food. There are numerous great recipes online, and most of them will still work well for crayfish. You may want to reduce the amount of shellfish and fish in the recipes slightly though, and increase the amount of vegetables.
Nuwan says
I’m Lost, i got one blue crayfish for 3 months (in a separate tank alone) now she is carrying black color eggs. i really don’t know what to do in this stage…. Ladies and Gentle, please advise???
Robert Brand says
There’s not really much you need to do at this stage. Just keep the tank clean, and her well fed, and assuming that the eggs are viable, they should hatch in the near future. After they hatch, and the hatchlings become free moving, you should the mother from the tank. Then you run into the real problem, since crayfish hatchlings are cannibals, and you either find homes for them all, or let nature take it’s course.
jessica wenger says
I saved my crayfish from my biology class. He is a 3 inches long and mostly brown with a touch of red. I bought him a 1 gallon tank with a filter, lid, a hollow rock to hide in and a fake plant to climb up. I have been feeding him blood worms, lettuce and carrots. He was covered in a fuzzy fungus so I used Pimafix to treat it -per the reccomndation of the pet Co employee. He has barely moved since day 6 of the 7 day treatment. On the 7th day I changed 25% of the water like the instructions said and he is still extremely lethargic… I’m worried he will be dead any minute now…. and has barely eaten in the last 24 hours. Could the treatment be causing this? I have had him for 8 days now and he was fine before!
Please help!
Robert Brand says
Treatments like Pimafix can be very hard on even healthy invertebrates. Once you’re dealing with a fungal infection, you quite often lose the fish or invertebrate that you’re treating.
With that being said, I would start changing the water regularly (around 10% daily), and remove any uneaten food. It may be that the crayfish is just having a hard time recovering from the treatment, so you may just need to give it time. Just keep offering it high quality food, and keep the aquarium clean. Good luck.
Danielle says
So heres my story me and my friends were cleaning out our stream and my friend finds a crayfish and thinks its a shoelace so almost steps on it she didn’t though. So we thought it would be cool if we kept it and guess what we don’t have anywhere to put it! What do we need to keep it? thx
Robert Brand says
At the very least you need a 5 gallon container of some sort. Then you will need to add a filter. Probably the cheapest and easiest to find is a sponge filter, though you have to watch out for it crawling up the air hose. Also, make sure to give it a few hiding places in the container that you’re keeping it in. Beyond that, you just need to keep it well fed, and change about 15-20% of the water each week (making sure that you remove the chlorine from water). If you do that, then it should be happy and healthy.
Rhiannon says
i found a crayfish earlier today in a ricer near my house and i plan on keeping him but as of now i dont have any food. Are there any household foods i could give it until im able to get some pellets? I put a couple leaves of lettuce in the container a few hours ago but so far it hasnt touched it. Also how often should it be fed?
Robert Brand says
It should generally be fed every day, though you only want to feed it small amounts and you’ll want to make sure that you remove any leftover food after 24 hours. Some of their favorite foods in my experience are lightly boiled zucchini or cucumber medallions, boiled broccoli florets and shelled peas. You can also offer very small amounts of salt water fish (ie. cod, tilapia, haddock, etc.) or very small pieces of shellfish like shrimp if you have it available. You need to keep the pieces small, or you’ll really foul the water though.
Also, they generally prefer to feed at night, although they can be trained to be fed very early in the morning, or later in the evening. I know mine tend to be most active after the lights go out in their tank.
Aram says
I have red crayfish and she’s full of eggs from her tail and I have 3 small fishes and one other male crayfish is it okay to leave them?
Ali says
Move female dwarf crayfish with eggs – How to
Can I move the female dwarf crayfish with eggs to a different tank? I see her juggling her eggs and I’m afraid that if I move her the eggs may come out? Any advice would be appreciated.
Robert Brand says
You can move her, but it can be hard on your crayfish to move it into an uncycled tank. If you move her, then you will need to change the water daily, at least until the conditions stabilize. Also, you may want to find a more gentle way to move her. If possible, try using a large container to gently move her out of her tank. A net may be too hard on her and the eggs.
Amy Priem says
Robert, thanks for all your crayfish knowledge. I am a third grade teacher and we teach with the FOSS kits. For the first time, we found a mama on Tuesday morning with eggs. We had worked with her on Monday so we have a pretty good indicator when the eggs were laid. Today, Thursday, we came to school to find another mama putting eggs under her tail. (Pretty fascinating) We have them in tubs so the kids can see them and work with them. We move them to a separate basin to feed them except for elodea in their containers. I have separated the mothers. How often should I feed them? Will the babies be okay in the basins as long as I put in homes and things for them to hide under??? The sad part is we will probably be out of school before any of them hatch.
Robert Brand says
That sounds really exciting for the kids. I always loved stuff like when I was in school.
They should be fed every day, but you will always need to searched for any food they have hidden during the weekly water changes and cleaning. The babies will most likely be eaten by the mothers if you don’t remove the hatchlings shortly after birth. They will still need places to hide from each other though, and you’ll still probably lose some to cannibalism unfortunately.
Jennifer says
We have a blue crayfish and we are getting ready to move, we have planned on rehomeing things out of our 30 Gallon tank. It is a big move.. we where wondering if our clam would be ok with the crayfish or if he would eat it? I can’t seam to find much information..
Robert Brand says
Most species of crayfish prey upon clams, and while I wasn’t able to find any specific references to blue crayfish eating clams, it’s probably safe to assume that they would have similar habits to their cousins. A good rule of thumb is that a crayfish will try to eat anything that it shares a tank with – be it plant or animal. I hope this helps.
kansascutiemom says
I’m looking for the post where someone mentioned hand feeding their crayfish. We have three freshwaters and I wanted to confirm that this is indeed true – I hand feed them all! It took me about two weeks to get them comfortable with the idea, maybe even less than that, but now they all come out on their own when it’s feeding time! 🙂 They hold up their larger pincers (nicely now – not in defense mode) and just wait for my hand. It’s so cool!! I’ve had many guests amazed by this little “trick” and its just one more thing I love about these little guys! 🙂 They are by far my favorite aquarium pets!!
danny says
Hey my blue crawfish had no then mate and all of a sudden it had a sack of eggs weeks pasted and it buried the eggs after that the eggs turn pink? And the crawfish died what do I do with the pink eggs?
Robert Brand says
They usually discard any infertile eggs, and when they begin to turn orange/pink, it usually means that they won’t hatch. This is especially true since they were discarded by the female. However, on the off chance that some might still hatch, the only thing to do in this situation is to keep the aquarium water clean, and watch and wait.
danny says
When I bought my blue crawfish, it was alone in a tank with a lot of tropical fish. Months had past since I had him and all of a sudden my blue crawfish had a black sack of eggs. The tank I had my crawfish was a 15 gallon, with two neon tetras. So my crawfish ended up burying the eggs after a while the eggs stated to turn pink, my crawfish ended up dying a few weeks later, but the pink eggs are still there what should I do?
Alexandra says
I have a really ill crayfish she is beautiful but has been itching like mad the last week and running around the tank like she is trying to climb out. it seems like she might have some irritating parasites under her belly and shes now become week from all the stress. Is there any medication I can add?
Robert Brand says
It sounds more like there is a problem with your water. Have you tested your water parameters lately? I would experimentally do several large water changes over the next few days to see if that helps, and I would definitely get your water tested.
I would also search your tank to see if there is anything rotting in there. I don’t know if your crayfish shares it with any fish, but a dead fish can negatively impact the water quality very quickly. And crayfish are also known to hoard food, so during the next water change, search to see if there are any hidden stashes of food.
There is also a small chance that your crayfish is starting to moult, but I would start with the water and if that doesn’t help, then you could proceed to looking into parasites. But most of the more common parasites that I’ve encountered are easily visible, and you would see what looks like small worms on your crayfish.
Alan says
i have had 2 crayfish in my tank.. they fight alot… and i want to know its okay if they keep fighting? and when can they breed ?
Robert Brand says
If they’re fighting a lot, then they will most likely eventually kill each other. You need to add ornaments and caves for them to hide in. More items in the tank will also help to break the line of sight, so they don’t see each other constantly. It’s also important to add caves, since the moment that one of them molts and has no where to hide, it will be defenseless and the other crayfish will kill it.
Tayla says
Soo hi I find this page very helpful since just yesterday I decided to raise one when my father caught one! I have a few questions to ask too:
If I place some live worms with the crayfish will the crayfish go for it???
I only have a small circle container with one crayfish in it, plus the rocks so it can breath. I believe the water won’t even fill up to 500-1000 grams of water! Any advice??
Robert Brand says
You definitely need something much larger to keep it in. I would recommend any type of non-toxic container until you find a more suitable home for your crayfish. They will eat worms (assuming the crayfish is large enough), though make sure you don’t over feed them. Also, make sure the worms haven’t been exposed to pesticides or insecticides. They actually prefer vegetables and maybe consider the worms as more of a weekly treat.
Crayfish can actually survive fully submerged in water, but you should add an air stone, or sponge filter if you can afford it. I hope this helps.
Tayla says
So thanks for the advice! I left some baby spinach leaves around it, and I found it kind of ripped apart, so I can’t tell if my crayfish ate it or because I left like that when I change the water, and then it just became too flimsy, so I’m concerned whether or not my crayfish is getting the food it needs.
Also, my parents were eating oysters, and they cleaned out and gave me one of the shells to use as a cave instead, and I believe it’s helped the crayfish a bit, since before it didn’t have anything to hide in(every time it sees me coming it scurries under the shell) so the container smells a bit of oyster.
Is this okay for the crayfish, since I had read that leaving shells in the same place as a crayfish can be bad for it. Also I don’t think I’ll be getting a big tank for the crayfish anytime since my parents wouldn’t go out and buy a tank for a single crayfish. Also, since the shell sticks out of the water, the crayfish fully submerges from the water when it chooses to climb on top of the shell. Is that bad?
And if i wash the live worm with water, will that wash off the pesticides and insecticides? I’m going to get the worms from a shop that sells live bait(worms) so do you think that’s safe enough?
Thanks so much for you time and patience! It’s much appreciated! 🙂
Ps, sorry for making you wake so early at1:48 am to answer this!
Robert Brand says
I would pick up some shrimp or invertebrate pellets if you’re worried about your crayfish getting enough food. They’re really cheap at most fish stores. But keep up with the vegetables. Just make sure to remove any uneaten vegetables after 24 hours or it will start to rot.
I haven’t heard of any problems with keeping shells in a crayfish tank. Where did you hear that? I’ve never done it mind you, but I can’t think of anything off hand that would harm the crayfish.
And it’s fine if the crayfish choose to submerge on its own. I find the problem only occurs when you do it for it, and even then it’s really quite a rare problem in my experience (air bubbles stuck in gills).
As for the baitshop worms, they’re most likely safe. Most worm farms wouldn’t be exposing them to toxins. The concern comes from collecting them outside in an area that may have been recently sprayed. And a quick rinse off most likely wouldn’t do anything to remove the toxins from a recently sprayed worm.
I hope this helps.
Tayla says
So thanks! I apologize for waking you up early again at12 am!
I feel a little better now. I’m pretty sure my crayfish is going along well.its become more active ever since day one! Every night I hear the scratching sounds of the crayfish at night. And my father uses minnow fish I believe for his bait, and yesterday one of his died, so I tried feeding my crayfish that and he gobbled it all up!
Is it alright if I feed him one most days of the week?
And do I need to clean the container once he’s finished? Because the whole container becomes foggy and dirty.
Also also!
After a few weeks of observation, I notice my crayfish do a funny thing.
You know those leg things on the bottom of her large tail? When she(96% sure) submerges from the water, she does this exercise where she just stays still, but her leg things(what are those called?) continuously run in the water. She’s on top of the shell, but her tail just unfolds and those funny leg things whose purpose remains unknown to me goes back and forth until she hears or sees something.
As much as it amuses me watching her do that, I would love to know if you know why. If you don’t, then that makes two:3
And i flip her over in the tank so the air bubbles escape. Will that help?
And thanks so much for listening on to my rambling! Your advice has helped lots!
Thank Ya!
Marlo says
We are deep in crawfish boil country, and our female red North American crayfish was a rescue 3 weeks ago from a big annual crawfish boil we always attend. Our sons (8 and 11) wanted to keep her, so she remained on the table while we ate, then went home in a tupperware container. That was 3 weeks ago. She’s the most interesting water pet we have, better than the inhabitants of our 10-gallon tank (4 tiger barbs, a golden mystery snail, and a vampire shrimp). I’ve gotten her to take food in her claw from me. Very cool. I had no idea a seasonal foodstuff could be such a good pet.
Have researched extensively but still cannot find answers to the following:
Do you know what it means when our crawfish approaches and waves all of her maxilla, or when she seems to do a little dance involving all of her legs? Sometimes she does both at once. I’ve noticed she seems to dance a bit after a water change. What is this?
She’s 4 inches head-to-tail, in a 2.5-gallon tank with 1 gallon of water, a large rock, and an artificial cave. The water is changed every day (we use water conditioning drops). Is this too often? Is this enough space?
Even if we add a filter, we can’t fill the water to the top as she’ll still need a place to come out of the water, correct?
We’re feeding her Hikari crab cuisine and algae wafers – both contain “calcium iodate” – + occasional broccoli. If she still needs to molt (at full size, do they still molt?) will she have the minerals to do so?
Would it be unhealthy to let her run around on the floor for a few minutes during water changes? Currently, we don’t, but just to offer more stimulation?
Thanks so much for hosting this site and sharing your knowledge. I’ve learned so much from the other comments and responses.
Best wishes,
Marlo
Robert Brand says
Hello Marlo,
Unfortunately I have no idea why crayfish dance, and I’ve never read anything to explain it. But you do see it in nearly all species of crayfish (though only very rarely in the dwarf crayfish for some reason).
As for your aquarium for your crayfish, it is definitely too small at this point. For a crayfish that large you should probably have around a 10-15 gallon tank, and it should be filtered. A crayfish doesn’t require any space to come out of the tank, and they are quite content living submerged in a larger tank with a filter. I like to use sponge filters since they are both cheap and excellent aerators. Also, when you do water changes, it will stress the crayfish out if more than 25% of the water is changed weekly. If you’re changing all the water daily, it’s probably not terribly good for the crayfish.
The food you’re feeding your fish should also be adequate for minerals and iodine for your crayfish. A lot of people use a marine iodine supplement for their crayfish, but all the research I’ve been reading recently points to that being ineffective on similar invertebrates (most of the research is on shrimp). It wouldn’t hurt to feed it a larger variety of vegetables though, and mine are always very partial to zucchini and romaine lettuce.
And it’s a bad idea to let your crayfish run on around during water changes. A crayfish’s gills take time to adjust between water and air, and while rare, it can get into trouble when added back into the aquarium. When transitioning from air to water, they should be placed in water no higher than their head for a few hours (a bucket works for this). After that, they can be added back to the aquarium, but they should be held upside down to allow any air bubbles trapped in their gills to become dislodged.
I hope this helps, and if I ever find out why crayfish dance, I’ll add it to the article.
Marlo says
Hi Robert! As a follow-up, our crayfish has been doing well. I did put a 76-degree heater in her tank, since her native LA bayou water never gets very cold, & in the upcoming months we keep our house at 65.
She had eggs, but gradually they all fell off. 🙁 We assumed that they had’nt been fertilized upon their exit from her body.
Now she’s molted from her bright red into a very dark slightly bluish red. My question is: Research tells me she should completely molt during a 24-hr period. This crawfish has been molting for 4 days. She lost a claw & an eye (seems to be growing the eye back?) – and her other new dark claw seems trapped in the old red one. Does she need outside help to free it? Or should we leave her alone?
Also, thought you might find her reaction interesting … We rotate different modern-sculpture-arrangements of common household red & blue items, or food packages with red & blue in the labels, in front of her tank, & she seems to be fascinated with them, staring as if checking them out, for hours. She loses interest after about a day, but then she’s always drawn to the new thing. 🙂
Robert Brand says
Sometimes crayfish have a rough molt, but you should definitely leave her alone. It’s too easy to do more damage rather than helping. You might want to try adding some iodine to the water in the future. It helps with the molts, and you can get marine iodine to add – though you should only add it at about half the recommend strength.
artwritewonder says
Thank you; I’m sure that would’ve helped. There will be a next time; she was a fantastically interesting and engaging pet. She died overnight.
Thank you so, so much for your advice and help. This board has been amazing. Have learned so much. Keeping a crawfish was a great experience.
Christy says
Hey Robert,
I have an electric blue with eggs that started out brown, but turned orange within a week or so. They will have been there for one month tomorrow. Is this normal? I saw your response to another post that orange eggs won’t hatch?
She’s in her own 10gal with sponge filter, eating a combo of frozen shrimp & sinking fish pellets.
Thanks!
Christy
Robert Brand says
It sounds like the eggs weren’t fertilized, or they ran into other issues. You can safely remove them at this point if she drops them. Otherwise just wait until she does, or she eats them. The eggs tend to die one by one, so it takes a while before they start to fall off. They usually start falling off one at a time.
Elisa says
We just acquired a crayfish…not sure what breed. daughter won it at school raffle. We have a small gallon tank, no filter yet and there is just a little bit of water…I assume for ease of transport. My question is how much water should I put in the tank and how often does it need to be cleaned, what kind of water (tap? distilled, etc?). It’s about 2 inches or so long. he’s been fed cat food up now. Can I feed it corn until I get other food? I am really clueless how to keep this little guy
Robert Brand says
You can fill the tank up to almost to the rim with no problem. Just make sure if you’re putting the crayfish from shallow water to deep water, to hold it upside for a while, so any air bubbles can escape from their gills. As for the filter, the cheapest choice is usually a sponge filter and pump, which you can normally get for around 15 dollars. It requires very little maintenance, and lasts for a very long time. All you have to do is squeeze it to clean it during weekly water changes.
The water can be tap water, but it should always be treated to remove any chlorine. You can buy bottles of water conditioner from any fish or pet store in your area. The crayfish may eat corn, but you should stick to lightly boiled vegetables like zucchini, cucumbers, broccoli, and romaine lettuce. Any leftover food should be removed after 24 hours so it doesn’t begin to rot and foul the water. You can also pick up shrimp or invertebrate pellets from a fish store, and just offer vegetables as an occasional treat. This is usually the easier option, and shrimp pellets are very cheap.
I hope this helps, and you’re in for a lot of fun with your little guy.
Elisa says
Thank you! I don’t think we have the right tank, so we may need to upgrade in order to put the filter on. The one we have is a plastic reptile tank. Also, is putting gravel down a good idea? Thanks again.
Krista says
Please help whoever knows. I work at a pet store and one of the blue lobsters has something going on with it. I didn’t notice or see any eggs as I had been off for a bit but it’s got these pink looking things under her tail, like the colour of shrimp. She’s turning in her tail as if she’s protecting them. I’ve seen a blue lobster carrying eggs before but haven’t seen this before. Is she pregnant? Or was she pregnant and the babies are dead? Is she sick? I have no idea.
Krista says
Also, if they are babies. Should I isolate her from the other? Need all the suggestions I could get. Thank all!!!!
Robert Brand says
It sounds like the eggs have turned, but otherwise the female still sounds alright. If by some chance they have hatched by now (sorry about the delay in response, I was on vacation), then they should be isolated as soon as possible.
Edwin says
We have had a crayfish now pregnant for over 3 months! What is happening and when will they hatch? Nothing seems wrong and the female looks happy enough…
Robert Brand says
What colour are the eggs? Usually a crayfish only carries the eggs for about a month or so. Healthy eggs should be a purplish black colour almost.
Edwin says
That is correct, nice almost blackish colour and all looks healthy. 3 months now … Are we breeding dinosaurs or?
Robert Brand says
Apparently. lol. What species of crayfish is it? I’ve really never seen one carry eggs that long.
Reen says
Hi robert, I have a white crawfish which molted approx 1 wk after purchase (expected), but, it then molted again within 2 wks! Reason???
Robert Brand says
How large is your crayfish? Very young crayfish molt quite regularly, thought usually slower than what you’re describing. It may just be that your crayfish is getting a lot of food and has very good conditions. Crayfish molt to grow their body, and if they have an excellent food source, they may grow quicker. If you crayfish is still acting normally, and all of your water parameters still look good, I wouldn’t worry about it. Just make sure to leave the discarded exoskeleton in the tank for the crayfish to consume.
Although, I have heard some anecdotal tales of crayfish molting when they’re stressed. But I haven’t been able to find any research to back that up, so take that information with a grain of salt.
Reen says
He appears to be young. Is in 37gal tank with a red and a blue female. He doesn’t appear to eat nearly as much as the females and he usually hangs out in top of plant. The 2 females have molted only once, and we can see the growth. However cannot see much of growth in male even after 2 molts. They were all almost same size when purchases. Purchased white male and blue female 1st; male use to move around bottom of tank. Then purchased red female. Since then, male usually hangs out on plant n away from bottom of tank (even though there are many hiding spots). Appears maybe he is stressed 🙁 guessing the females are ruling the roost! 🙁
Reen says
He Robert, wanted to say thanks for your help and that your site was very helpful; and, that 2 days ago our white male crawfish passed away 🙁
Robert Brand says
I’m sorry to hear that. It always sucks losing a crayfish. They’re so full of personality I can never help getting attached to mine.
Willie says
Hi my son got a crayfish from his teacher just before the end of school. It lasted till the end of July. I think it died because it was out of water for a long period of time and also got hurt. It had escaped during the night and my son found it in the morning when he was about to feed it underneath the china in the dining room. It was the second time it escaped but the first time from a 5 gln tank and it had grown. We quickly placed it back in the 15 gln tank and watched it during the day. During the afternoon, we noticed it went close to the hanging filter and started its way up the wall. I think it has a damaged claw because it took off its left claw. It stood around around after that just looking as if was sitting on its curled tail but we saw movement so thought it was sleeping. The next day, it was in the same position but not moving, my wife went to check on it by reaching for it but did not move and was stiff. Not sure if I should get another one for my son. Him and his younger sister liked seeing it and they assisted in the care (he’s 9). It was not his fault it died, it just escaped and fell four feet to the ground then crawled under the china with a bad claw. Should I or shouldn’t I?
Robert Brand says
I’m a little biased since I think crayfish are great pets. It’s unfortunate what happened, but at least you can learn for your next one. The first thing to do is to cover your aquarium with a fish tank cover since they will always try to escape. I’ve actually had numerous escapees in the past.
One thing to be aware of though is that when you put the crayfish back in, you need to put it in upside down so any bubbles can be purged from their gills. They can get in trouble if you don’t do that. If you don’t want to do that then you could set up the tank in a way where it it has a ledge it can stand on outside of the water, and it can handle it’s own immersion into the water.
I personally would always recommend these pets, though they are somewhat shortlived. Most will only live a few years, so that’s sometimes hard on younger children if they get attached.
Kelly says
I have a 90g pond with 10goldfish. I have noticed crayfish in the pond that have a blue color. I have one that got in there, not sure how as it was covered with a net. That one died and now there is another one and we aren’t sure how and/or where they are coming from. Any ideas? We thought maybe a owl dropped one and it fell in the pond. These do fine with my goldfish and the frost crayfish was in there for 2years. We just can’t figure out how and where they aren’t coming from. Any help is appreciated
Robert Brand says
Crayfish are known to travel long distances over land, and if you have any streams or ponds nearby, they may be coming from those. If they’re not a native species to your area, someone may have released them, and they found their way to the nearest body of water. This is more common than you think, and a pond near my house is home to a bizarre array of tropical species people are constantly dropping off when they don’t want to care for them any longer. But since it’s Canada, the winter tends to wipe them all out so they generally don’t become a problem.
everlyalvarado says
Hi, we bought new crayfish and after three days we notice there’s a bunch of eggs attached to her tummy. So we separate her quickly into 10 gallon fish tank. I can’t remember the exact days but I think after 3 weeks the eggs hatched. The mom still alive and we put it back to big fish tank while the babies left here in 10 gallon fish tank. The babies separately hiding into gravel. I smashed moms food and feed it into babies. Am I doing it right?
And one thing, is my guppies safe from that mother crayfish? Thanks
Robert Brand says
It sounds like you’re doing a good job. Just keep on top of the water changes, and continue to offer them easily consumable foods, and the babies should be good. You will eventually start to face some cannibalism among the babies though, so depending on how many you want to keep, you might want to start separating them into other tanks. That’s not always feasible though.
And as for the guppies, in my experience nearly every species of crayfish will attempt to eat the fish they share an aquarium with. Eventually it will likely start to pick off some of your fish. The only saving grace for fish is that crayfish usually aren’t that skilled at catching them.
danica muroff says
my crayfish is doing awesome from your advice thank you!!!
Robert Brand says
That’s great to hear. Spread the word, so we can make this pet more popular.
Lovingthesepets says
So I just got crayfish the other day from the river down the road. I’ve already fallen in love with them. The thing is one is female one is male I figured that two males would be more territorial. The male was aggressive but then the female molted and is now much bigger than the male. Will she want revenge and eat him after he molted? I just really don’t feel like waking up to my new favorite pet shredded.
Robert Brand says
How large is your tank? As long as you provide numerous caves and other places to hide, it should be alright. A crayfish is smart enough to know to hide when its molting, but if you have a very small tank, it may be discovered.
Cody says
Hey Robert my crawfish hasn’t been eating I caught him in a creek 2 days ago and he doesn’t like frozen veggies and he doesn’t eat fish what should I do? Oh and he isn’t aggressive at all
Robert Brand says
It can take a crayfish a while to adjust to its new habitat. It may just be a bit stressed by its new surrounding, and I wouldn’t worry to much if it doesn’t eat for the first week or so. However, just to be on the safe side, I would check your water quality, and try offering it a few different foods types, like maybe shrimp pellets, or some frozen food like brine shrimp or blood worms.
Lea Insalaco says
Hey will a red freshwater lobster breed with a blue one?
Robert Brand says
It is my understanding that those species won’t interbreed, though many crayfish native to North America can cross breed.
Lea Insalaco says
Hey, I got a few questions this time. I just cleaned my community tank and was a bit surprised to find 5 baby crays in it! I knew I had a male and a female, but I thought she had killed and eaten him during one of his molts. Apparently that’s NOT the case as I also found him during the cleaning. She’s still a pretty reddish brown with white spikes all over but he’s changed color. Now he’s paler and his legs have turned Blueish. Most of the babies seem to be in colors of blue too. Is this odd? The babies are several different sizes ranging from just under and inch to over 1.5 inchs. I put the smallest into my guppy tank since I know they are canabalistinc and he’s gotta be on the menu for everyone. The rest are all back in the community tank. Will they all be okay in there? It is a 40 breeder with about 1/3 of the tank taken up with a large stack of stones for the turtle to get up on to sun himself. there’s at least 3 den sites in there and I made a few smaller ones in other locations too. It’s got really good filtration, undergravel + a fully subermisable quietflow 40. There’s tons of vegitation, I replant the tank every time I do a full cleaning which is about twice a year. I do throw more plants in occasionally between cleanings and I grow water lettice in my outdoor pond to bring in. All occupants seem to enjoy eating that. Aside from the turtle, mom and dad cray and now the 4 largest babies, there’s also 3 largish goldfish, 3 angelfish, 2 small catfish and 4 large danios. Will it be too crowded for the babies to stay? I also throw in 2 dozen rosy minnows every week for Sheldon, the turtle, to eat so he doesn’t eat my other fish. I know the crays have been getting some of those too. Should I be getting more minnows? Am I providing enough food? Anything else I should be doing that I’m not thinking of?
Robert Brand says
Hello Lea,
Unfortunately, it sounds like that tank is really overstocked and with fish that have really different needs. Goldfish prefer cold water, and depending on the species of catfish, most of the other fish like tropical temperatures in their tank. Also, turtles produce incredible amounts of waste, and it would be hard to keep that size of tank clean just for the turtle (unless you have one of the smaller musk turtles, which are great pets by the way).
The crayfish will also be on the menu for everyone in the tank until it grows larger, and then the tables will be turned when they’re large enough to prey on the fish. I know it’s expensive, but in the future if you can afford it, I would recommend a turtle only tank (though they do well with larger goldfish too), and then a separate tank for the rest of your fish and the crayfish. But just keep in mind the crayfish will always be trying to eat the fish as they grow, and the fish will try to eat the crayfish during molts.
Lea Insalaco says
My tank has been like this for years, water quality is really good and all inhabitants get along well. They adult crayfish are about 6″ long which is bigger than the turtle who is only 3ys old. We got him newly hatched from a nest in the backyard. He may have eaten some of the babies, but that was hardly unexpected. I did put the smallest 2 babies into other tanks with guppies that I don’t care if they steal a few of. You are correct about the goldfish preferring colder water, but they started out as tiny feeders for sheldon and they got big before he got around to eating them. I did ate all but 2 goldfish out and put them in the outdoor pond. Both sets of goldfish seem to be doing well enough and everything else is a warmer water fish so I keep the tank at about 76 degrees. With double filtration and a full ecosystem setup I rarely even get algae growth in my tank and only pull it apart to clean it 2 times a year. The fish clean up after the turtle, the crays and catfish clean up after them and the plants do the rest.
Robert Brand says
That’s great all of your fish are doing well. I was just giving a suggestion though for the future. And I’ve had some feeder fish setup colonies in tanks before, and I had some fathead minnows start a colony in my small mouth bass tank which lasted for years (I used to keep native North American species for a while there).
Lea Insalaco says
That’s awesome! So seeing as how I am not having water quality problems, and nobody seems to be eating anyone not intended to be eaten, will 6 crays be ok in that tank? there’s 8 densites and they all seem to share and move around. the 4 babies still in the tank with the parent are all female as best I can tell. Thanks for the post with the pictures for how to be sure about that BTW, it’s been really helpful! If I can’t have 6 in a 40 breeder tank, I don’t mind rehoming some or all of the babies. I have friends and even a local pet store interested in taking them once they are 1.5 inches or larger and 3 of them are that big now. Any idea if they will stay blue? I am still rather perplexed as to why the dad’s lower half turned blue and why the babies are all blue. As long as they are healthy, I’m happy. I don’t really want to stress them out by leaving them in a tank too small to hold all 6 of them. Also worried that dad will breed with his daughters once they get past the 3-4inch size. Will they do that? or will he not breed with them seeing as how they are his offspring? I cant see a crayfish being that particular and I’m not really wanting inbreeding…… Or massive quantities of babies…..
Robert Brand says
I would try to rehome at least a few of them if possible. Depending on the setup of your tank, there likely wouldn’t be enough hiding places for all of them, though that depends on the setup of your tank.
And crayfish turning blue is a mystery as far as I know. I’ve read some research papers where crayfish turn blue in experiments in universities, and even the experts don’t really know what causes that colour change. It seems once they turn blue, they will remain that way as long as they remain in the same conditions. I’m hoping to learn someday why they do this.
Mr Boo says
Hi Robert.
Thanks for this awesome site. I’ve used the valuable info on this site a few times now, but I could really do with your help. Until recently I had 2 blue crayfish. I’ve had them for about 6 months, and they have been doing really well, and growing loads more than I imagined. We kept them in a large tank with other fish – unfortunately we learnt the hard way that crayfish and plecos don’t mix. Let’s just say the crayfish won. But they are ok with the mixture of tetra’s I have in there. Anyway, the problem I have is one has gone missing and the other has eggs under her tail! I’m not sure if the missing one has been eaten or somehow managed to escape, but I am not sure what to do about the prospect of having a hundred tiny crayfish eating all my other fish. What do you recommend I do?
Robert Brand says
I’m really glad you’re enjoying the site, and I’ve faced this same problem numerous times. Sometimes fish or crayfish just go crazy with breeding, and you’re left trying to figure out how to house dozens of hundreds of hatchlings or fry. I wouldn’t worry about the fish though. If you decided to leave the crayfish in there, it’s likely the fish and adult crayfish would eat most of the crayfish hatchlings. And the hatchlings themselves become cannibalistic as they age, so that will reduce the numbers even further.
If you want to keep them though, you’re going to have to set a separate tank. After they hatch and are free swimming, the mother should then be removed too. As they age, you’ll have to continually rehome them to provide them with the maximum amount of space. The good news is there is generally a lot of demand for blue crayfish You can sell them on local fish forums, trade them for credit at fish stores and if that fails, you can usually give them away.
And as for the male, in my experience they tend to disappear when the female becomes egg laden. I haven’t found anything regarding this in literature, and I don’t know if it’s just my personal experience, but I normally find them hiding a short while after the eggs have hatched. But take that advice with a grain of salt, and it may have been eaten during a molt or pulled a houdini on you.
I feel your pain with the pleco too. When I first starting keeping crayfish, I lost a lot of fish trying to find tankmates for them. I even had a friend who lost an adult arowana to a crayfish. I have no idea how that happened. I eventually went with crayfish only tanks, as it seems to be the least trouble that way.
Mr Boo says
Robert, Thanks for replying. It’s great you have a wealth of experience here.
Unfortunately we found the missing male crayfish earlier this evening after my dog was sniffing around underneath the tv cabinet. There he was behind some wires on his back. I’d somehow missed him when I searched the other day. Poor thing has passed away, although I currently have him half submerged in a bowl of warmish water. I am hoping somehow he has survived and magically comes back to life, but honestly, I can’t see a happy ending. I’m actually quite sad about it as he was a lovely looking thing, and quite big at about 5 inches long. Ah well, at least the female is still around. I am going to make some mods to my tank to ensure she can’t escape.
As for the hatchlings, I’ll probably separate them, and then see if the local fish shop will take them in as we don’t have the capability to house lots of tiny crayfish. I might keep a couple back but will see how it goes.
I’ll let you know how we get on….It’s about 4 weeks before they hatch isn’t it?
Robert Brand says
The eggs usually hatch after around a month, and then your tank will be swarming with little hatchlings. I feel you pain with the crayfish, as I lost a really big one a few years ago to an escape. In that case my dog actually brought it to me in its mouth.
Let me know how the hatching goes. I’m looking forward to hearing about it.
Shawn says
My crawfish aint breeding at i have a male and female what should i do
Robert Brand says
There’s not much you can do to encourage them to breed, but you can make sure the conditions are as perfect as possible. Increase the frequency of your water changes to make sure the water is sparkling clean, and feed them a very high quality diet, which should include blanched vegetables, shrimp pellets, and frozen foods (daphnia, bloodworms, etc). While neither of these things will trigger breeding by themselves, clean water and high quality food will encourage breeding behaviors.
Certain species also need a trigger like spring to start breeding. Assuming you don’t have a tropical species, you should try lowering the light period and the temperature. Then over the course of a few weeks, slowly increase the temperature of the water, while increasing the amount of light in the tank. This simulates spring, and may trigger breeding in certain species.
jeremy paul says
I have a 4 red belly Pacu (1 5 inc big and the 3 are just 3 inches big). I am thinking of getting a Crayfish for my 7 year old daughter to see and enjoy. I am planning to put those articles that I heave read to action (cave, pots on it side and stuff). My main concern is would by Red belly Pacu slaughter crayfish? I have not seen any posts regarding this. Also, I have a Common Pleco whos is also a bottom dweller, should I remove it to make room for my Crayfish (assuming they can live with red belly pacus)?
Robert Brand says
Though Pacus mainly eat nuts and fruit in the wild, they will supplement this diet with just about anything that moves. And since they can grow up to 3 feet in length (0.91 meters), most of them can make short work of a crayfish. And if it doesn’t, depending on the species of crayfish, it may attack the pleco since bottom dwellers are especially vulnerable to them.
If you want to keep fish with a crayfish, it’s best to stick to smaller fish like barbs or tetras and to stay away from any bottom dwelling fish. And even those can be at risk, depending in the crayfish’s temperament and species.
jeremy paul says
Thanks Robert.
Jason says
I have a blue crayfish in a 30 gallon tank with a pair of koi. I just noticed she is pregnant and loaded with eggs. Can I keep her in the tank with the koi or will the koi eat the babies?
Robert Brand says
The koi will definitely attempt to eat the babies, though their success will be determined by how many hiding places there are. You can also expect to lose a lot to cannibalism among the young too.
Rebs says
My son got given a fresh water crayfish. She had eggs attached after set up of her new home four days later i noticed she was moving about to much and came in this morning and she was not alive. What can i do with the eggs? i have left her in the tank and have the filter running over the eggs. Can i save the eggs? Not to sure how long she has eggs for. HELP.
Robert Brand says
Without the mother, the eggs likely won’t remain viable. But the best thing you can do is to give them the cleanest water possible, and watch for any signs of fungus. Fungus is often the real egg killer, and any hint fungus, you should treat with tea tree oil. Unfertilized eggs often succumb to fungus, so if they eggs aren’t fertilized, you may quickly lose all of the crayfish eggs to fungus.
Amaros says
Thank you for writing this! If I caught a crayfish to put in our well circulated 1 foot deep (kind of natural-we just helped it a little)pond, well planted, 8 by 5 foot pond, would it survive? Would I need to feed it? There are a couple of fish in there that I don’t mind getting eaten. Also, would a crayfish eat watercress?
Thanks!
Robert Brand says
Assuming it comes from the same climate your pond is in, it should do very well in a pond like that. Though don’t be surprise if it doesn’t like its new home, that it wander aways. They will often travel across land to find more suitable homes. They also can consume vast quantities of aquatic plants, though I don’t know if one crayfish would be able to consume all of the watercress in a pond like that. Especially since there will likely be other natural food sources occuring in the pond and it may forage around the pond on land.
Chontelle says
Can crayfish be unisex?
Robert Brand says
As far as I know, the Marbled Crayfish, or Marmokrebs (Procambarus virginalis) is the only know species of crayfish to reproduce via parthenogenesis. All the of the crayfish are females, and they were introduced to the hobby in the mid 90s. There is no information on where they originated, and there are no known wild populations currently (though they are believed to have been introduced by release in certain areas).
Marlo S. says
Didn’t know that! So I looked it up. More on Marbled Crayfish, for anyone who wants to know: http://faculty.utpa.edu/zfaulkes/marmorkrebs/ 🙂
Natasha says
Good day
if your crayfish has eggs does this mean the eggs where fertilized
thank you
Robert Brand says
Many crayfish will have eggs without them being fertilized. However, most species can store sperm for up to six months, so when was the last time she was around a male? If the eggs are infertile, she will eventually realize this and will consume the eggs.
billie says
Hi, I was wondering if you could help me. I just got an electric blue lobster and he seems to have little clear worms on him. What can I do about this? We are already in love with him and don’t want to hurt him by doing the wrong thing, thanks.
Robert Brand says
Generally speaking, most of these worms are pretty harmless to the crayfish, and I’ve in certain places they are even beneficial. They are new ubiquitous in wild caught crayfish, but I do understand they look very unsightly.
One way to get rid of them is to remove the shell after the molt. This will usually prevent them from travelling over to the new exoskeleton. If you want to be a bit more aggressive, then you can use something like PraziPro, which will usually kills all the worms in the tank.
Adam J says
Hello, I am considering getting a crayfish for my tank but from what I have read might be reconsidering. I have a 55g tank with over a dozen fish, including 4 2 year old Angel fish, and a one year old Pleco, two small barbs, neon tetras and ghost catfiah. The aquarium is also heavily forested but has multiple rocks and small alcoves with gravel/sand below. The top is lidded and has a sponge filter. My concern is, would this set up be an an all you can eat buffet for the crayfish/fish, or an environment where he can hide and do his thing?
Robert Brand says
A lot depends on the species, but I always advise people to be very wary of adding a crayfish to a tank with fish. You’ll hear from plenty of people who’ve never had problems with crayfish, but the few times I’ve tried have been disasters. And with larger fish like angelfish, you run a real risk of the angelfish turning the tables and eating your crayfish when molting. In my experience, it usually comes down to who gets eaten first – the crayfish or the fish.
Also, they’re voracious plant eaters, so you could say goodbye to nearly all of your plants if they’re live plants.
Sharpkitten says
Hello- I have an orange and blue cray- and they are male and female- been in together now for about 6 months- I am wanting them to breed but they don’t seem to be- I’ve read about them being in phase after they molt and they had molted around the same time so I am wondering what I am doing wrong ? Thanks great forum by the way
Robert Brand says
Have you seen any mating occur? Do you have to know the exact species by any chance? Have you noticed any sperm packs? Is the orange crayfish a dwarf crayfish?
Willie says
Hi Robert, quick question. I have a blue crawfish which was very active and ate very well for the past few months we’ve had it. Recently, it has not been eating its pellets that we always gave it, and it stays hiding under its dark tube. It’s alive but not active and seldom comes out to eat. Should I changd the food to actual fish to see if it starts to eat regularly, or is it a sign that it’s not going to last much longer?
Robert Brand says
How long has it been acting this way? If it’s only been a few days, then it may be preparing for a molt. If it’s longer, the crayfish may be ill. What are your water parameters like? The only thing I could recommend is adding some half strength to quarter stength marine iodine to the tank, in the hope that fixes him. In my experience, it tends to be extremely difficult to treat an ill crayfish. I hope he starts to recover.
Willie says
I know this will be long, but I don’t get it. The water has always been at 72•-74• and w/a good filtration system. I went ahead and purchased two medium size and two small gold fishes (.12 cents each) for him to catch and try to eat, I figured he outgrew pellets and needed real food. He was out of his tube when I put the fishes in his tank. At first he stood frozen as if he was shocked with his claws owned and in a position ready to attack. But he didn’t. The fishes swam around, in front and behind him and he did not move. One fish even swam to his mouth and tapped him causing him to jump as he was surprised. About an hour later, I found he was trying to escape the tank and had his claw caught in between the filter and cord, I tugged the cord down to let him loose and he slowly just walked to his half opened barrel. As of today, I still notice he’s more active by getting out of his hiding spot to walk around but does not chase he fish. They even swim or stay with him in the barrel when he’s in there. He acts like they are relatives and friends and does not bother to hunt them. I really don’t get it. My wife said how he’s been moving around more, she threw in a pellet but noticed some of the fish at it. Today it was gone do we don’t know if it was him or the fish that ate it. I’ll throw in another pellet in tonight and monitor who’s eating it.
Robert Brand says
It sounds like he was just stressed from the new additions to his tank. Crayfish and fish have a very strange relationship sometimes. Some of them will live in complete harmony, and others will turn an aquarium into a scene from the Texas chainsaw massacre within minutes.
Another problem is that crayfish are either the predator, or the prey, and larger fish like goldfish will sometimes eat crayfish. Still, just give it time, and often the crayfish will learn how to catch the fish.
CAPTAINPRICE79 says
Do you know what kind of Crayfish this is? If so‚ what’s it’s preferred diet/tank requirements?
https://goo.gl/photos/Fb6MMX18fjL8hhaQ7
Robert Brand says
All comments have to be approved individually, so I can protect against spam. But as for the crayfish, it’s hard to tell just by looking at it. Was it wild caught, and if so, where? Was it purchased at a fish store? If you give me a bit more information, I can help narrow it down.
But most crayfish have pretty similar dietary needs. You can usually meet them by following the feeding guidelines in the article. Just make sure they blanched fresh vegetables, shrimp pellets and maybe the occasional frozen fish food, and you should have a happy and healthy crayfish.
krishemard says
Wild caught near the Ohio River Valley, 32 or so miles north of Louisville, Kentucky. I bought three minnows for it since the pet store in the town was closed and I didn’t think it would sell Crayfish food or anything. It seems to have ate two of them, but I’m unsure as every time I try to check the hiding places, the Crayfish lunges forward and I have to remove my hand for fear of being pinched. I handle snakes with bigger weapons and stronger application force every day, but I’m scared of getting pinched by a Crayfish. There’s a certain irony to that somewhere, I’m sure of it. But I’m positive it ate them, as they tend to avoid the hiding places. I’m uncertain of the species, so I don’t want to make the water too warm or too cold, since I don’t know what would happen to a cold-water Crayfish if I put it in warm water, or vice-versa. I’ve tried looking up the Crayfish of the area I found it in, but none of the pictures look like it, and I’ve looked at ALL(all caps meant for italics) the species I’ve read on the Indiana-oh, wait. Okay, so it appears similar to some of the Painted Hand Mudbug I’m seeing, but a majority of the Crayfish shown are blue, so I’m not 100% sure. Also it lives in a cage mostly devoid of objects to hide in save for two fake rocks, and a pile of thoroughly cleaned gravel rocks, though he avoids those. This is mainly because, as I literally found this website AFTER I put it in the water and stocked the rocks and filters, he became incredibly hostile and I couldn’t get to him without threat of very, very painful pinching. He also hid in one of the fake rocks when I tried to grab him for almost thirty minutes, so I couldn’t retrieve him. He’s been in it for a few days though, so I think he’ll be fine.
TL;DR
I have no idea what I’m doing and I need help. I also believe it may be a Hand Painted Mudbug.
Robert Brand says
I think it definitely falls under the Orconectes family, but there are so many crayfish native to Ohio, it’s difficult to tell without really examining it.
And you’re not the only one to have a dislike for those painful little claws. It must be instinct, because the second you them coming at you, all you want to do it avoid them. And I’ve been handling them for years, and I still pull my hand back at time without realizing it. I actually handle mine with rubber gloves, when the water level is low during a water change. It’s also the best time to add hiding places and whatnot for it.
And don’t worry too much about the temperature. As long as it’s in a heated room, I believe all the crayfish species native to there will be fine with room temperature.
And you sound like you’re doing fine. You’re reading up on it, which is more than 99% of the people do. Just switch the diet over to some sinking pellets, and start adding some fresh, blanched vegetables and you should be set.
krishemard says
Here’s the cage. /Users/kristopherchemard/Downloads/IMG_20160212_122157_569.jpg It’s not permanent, but he’s behind the structure to the left, and there’s a minnow under the bubbler for food. He ate two shrimp pellets I bought a few hours ago right in front of me, so I’m sure he was hungry. Not sure if he ate anymore, since the pellets he ate landed within an inch of his main claws. I will probably add some sand and more rock, so as to make it feel more like a creek bed, since he was wild-caught. Is this a good idea? If not, is there another way I can make it feel like a creek bed without sand and some rocky hiding places?
Robert Brand says
You’d have to upload to the picture to a picture site and then link it from there. I can’t see the link you posted (it’s from your computer).
And I think the sand and rock are great ideas, as long as you’re careful what type of sand and rock you add. You’ll only want safe sand, like playsand or the like, and you’ll want to wash it in a bucket until it runs clear. And you can read about safe types of rocks and how to add them here – http://aquariumtidings.com/adding-rocks-to-aquarium/
krishemard says
Hey I’m back. My crayfish is starting to get green on it’s two large pincers. Is this a sign of molting soon or will Leonardo diCrabrio bite the dust soon?
Robert Brand says
Do you happen to know what species it is? When you say green, is it a mild colouration, or like something is growing on it?
Anna says
Hi,
My son was gifted a crayfish from school and I am in the process of securing it the proper home. I’m thinking a 10 gallon tank will suffice, though how much water should be added? I’ve had a Tiger Oscar Cichild that I would hand feed – an awesome fish! – but this will be our first venture into crayfish ownership. Thanks in advance for your help.
Robert Brand says
The aquarium can be filled to the top for the crayfish, although you need to make sure there isn’t anything is can use to climb out if you don’t have an aquarium lid (and even they, they’ve been known to escape). Also, if they’ve been out of water, hold them upside down (with the benefit of thick gloves if you haven’t handled crayfish much) so any air bubbles can escape from their gills. If they’re out of water for any period of time, air bubbles can form, and they also need time to readjust their gills to water.
And crayfish are an amazing pet to keep. Just make sure you provide it with lots of hiding places, and it should come out pretty regularly for you.
judith says
I am going to put in a wild crayfish in my 20 gallon tank with my chiclinds how can i declaw him?
Robert Brand says
I wouldn’t recommend that. It’s best to just give them their own space, so you don’t have to injure them.
Lea Insalaco says
DECLAW a crayfish? Like yank his arms out of the socket, and do it AGAIN and AGAIN when they grow back? That would be an incredibly cruel thing to do. There’s no way to even anesthise him!
Soma says
How much water do you put in the crayfish aquarium? Ive heard only an inch. is this true? I have one crayfish and a 10 gallon tank. I bought something to pump air in there too-it’s a pump with a tube that bubbles. Any other things that I need?
Robert Brand says
You can completely fill the aquarium, and I would recommend using a sponge filter instead of an air stone, since you want to filter the water. Beyond that, add some decorations, or clay pots on their side for the crayfish to hide in. With that, you should be ready to go.
electronicsurgeonSoma says
Are you saying that I can’t use the airstone? And why a sponge filter?Will it give air to the water? I think I’ve read NOT to use a sponge filter(maybe I’m wrong).
Robert Brand says
No, you can use an airstone, but I find sponge filters better since they also filter the water. An airstone will only aerate, and doesn’t have enough area on it to allow beneficial bacteria to grow. They are what keeps the water safe for the crayfish.
I don’t see why you shouldn’t use a spongefilter. The only possible concerns are the crayfish climbing up the air house, or on rare occasions, a crayfish may take a chunk out of the filter. Beyond that, I can’t see any possible problems and I use them in all of my crayfish tanks.
electronicsurgeon says
I couldn’t find a sponger filter, so i used a carbon filter that u put on the side of the aquarium. I hope that is fine. Also, any idea how to get zucchini and cucumbers to sink and not float? Also, what are other things that I can feed this crayfish? And do I need to really need to add iodine or calcium, or can my crayfish survive with me providing him the right foods? Sorry for all the questions 🙂
Robert Brand says
A carbon filter is fine, and actually does a bit better job of cleaning the water. But just make sure the current isn’t too much for the crayfish, and there are areas where it can sit comfortably.
There are two ways to get the zucchini and cucumber to sink that I’ve used in the past. The first is to boil it for a while until it become soft, and then it will sink naturally. If you’re afraid of losing nutrients by boiling it, then you can either buy a clip at the fish store that holds it to the side, or you can use a plastic fork and spear it, and then drop it in the aquarium. It’s not pretty, but it does the job very well.
Calcium it should be able to get from the food, but you might want to consider adding marine iodine at around half strength. I know many people who get away without doing, but it does seem to help crayfish in my experience.
Mark says
I saw a video on YouTube from a person who had a backyard crayfish pond. For ‘caves’ he used PVC pipe. I’ve read in the comments above about terra cotta pots or river rocks as a hiding place. Would PVC pipe or joints be an acceptable ‘cave’ for a crayfish in a tank (10 gal) or would there be a concern about some sort of chemical leakage?
Robert Brand says
PVC is totally fine for an aquarium, and you can actually make nice, natural looking caves out of it. The way I do it is to put a layer of aquarium safe sealant on the PVC pipe, and then add rocks to it. Or you could also add a layer of sand, or gravel that matches your existing substrate.
Just make sure to let it completely dry before you place it in your aquarium.
Mark says
Awesome advice – I think I will give it a try adding rocks to make it look more natural. Thank you!
Lea Insalaco says
Don’t forget a well fitted lid with no holes larger than 1/2 the size you think he’d fit through…. they are escape artists and will climb up and out using the airline from your sponge filter! Or anything else that gets within 5-6inches of the top. My 1st one got out 3 times before I got it so he couldn’t escape anymore. He almost died! TWICE!
Napadon Yinfeemark says
HI I would like to buy some breeding crayfish can you tell me where to buy . I live on Melbourne my name tong
Australia or you can call me on
Robert Brand says
Sorry, but I live in Canada and I don’t know any distributors there.
Mark says
My son purchased a Blue Crayfish from the store and we brought it home. Approx. three weeks later my son notice eggs underneath of it! We were very excited! We’ve been watching them for about two weeks now. Two days ago I took a picture to show my friend (see imgur link below), then very next day there were NO MORE EGGS and no baby crayfish!! That was yesterday and after another careful look that are definitely no baby crayfish. What happened?! Do crayfish abandon their eggs?
http://imgur.com/6ZRPcgs (sorry for the blurry image)
Robert Brand says
The mother will often eat the eggs if she is under stress, or if they are infertile. It helps to recycle the nutrients for its next breeding attempt. Most species can store sperm for long periods of time, so you may see eggs again in the future.
Kima Caddell says
Do crayfish have any specific light needs?
Robert Brand says
I’ve read that bright light can stress them out, although many scientists disagree that they can even feel anxiety. So the best thing to do right now is to give them an environment with muted light, and provide plenty of caves they can hide in.
Dolv says
do crayfish eat mealworms?
Robert Brand says
I have to assume they would, but they’re awfully large for a crayfish. You’d probably have to clean out the leftovers so it doesn’t foul the water. I usually stick to smaller food like frozen bloodworms, daphnia, brine shrimp cubes etc, if you’re looking to feed them something meaty.
ahoynecko says
Hey! I’m hoping to soon own a crayfish myself and had a few questions I’m a tad confused on. I was wondering if I should set up his tank similarly to my fiddler tank (partial land partial water). I’ve read mixed information that says if they are fully submerged they’ll drown and others that say if they aren’t they can suffocate. I was also wanting to give him my over growth of plants, are there certain kinds he cannot have? And for feeding, how often should I feed him and what? I’ve read that it’s best to change up their diet and use different foods on different days, and for enrichment, to throw a few live fish in there every so often. I breed feeder fish for my fiddlers already but I’m not sure how many I should drop with my crayfish at a time. Thank you for this article!
Robert Brand says
They definitely don’t need a partial land/water tank, and they’re perfectly happy with a full aquarium. But with that being said, you do need to be careful when adding them to water if they’ve been out of it for any length of time. They will first need to be put in water that’s no higher than their head so they can acclimatize to it, and then they should be put into the tank upside down, so any air bubbles on their gills will become dislodged.
It’s also a very important to have a filter or air stone to aid in gas exchange in the aquarium, which will provide the crayfish with needed oxygen.
When you say overgrowth of plants, do you mean aquatic plants? Because I’m not aware of any that would be toxic for crayfish, though I’ve only tested the more common plants, so try to stick to plants like elodea, water wisteria, etc. If you don’t mean aquatic plants, then there are many poisonous house plants, so I would steer clear of those.
And you should feed you crayfish once a day, with treats every other day or so. The main diet can be composed of sinking shrimp pellets, while it appreciates the addition of frozen foods like worms, and regular offerings of blanched vegetables as treats. Make sure to check it’s cave every week though, as they have a tendency to hoard the food here.
As for fish, I wouldn’t really bother feeding the crayfish any live fish. They should be able to get most of their nutritional needs from the diet described above, though you may want to add a quarter, or half strength marine iodine to the tank now and then. Fish end up creating an awful mess in the tank, and the dead fish will probably foul the water pretty quickly. It’s something you can do, but it’s really more trouble than it’s worth.
ahoynecko says
Is there any Benefit to having a full aquarium over a partial water set up? And with enrichment I was meaning activity wise not so much nutritional. The breeder I am buying from had them full submerged I believe. But I wasn’t sure if there was any benefit of one over the othe
Robert Brand says
There is a significant benefit as a larger quantity of water will be far more stable and oxygen rich, than just a small pool for the crayfish. Also, it tends to be easier to clean, as it’s difficult to clean shallow water properly without completely changing it out – which is never a good option when it comes to crayfish or fish. It’s always better to do small water changes, to maintain stable pH and water parameters. While crayfish aren’t nearly as effected as fish, they are still affected by rapid water changes.
KellyDown says
I live in Southwest Washington and gathering information on aqua farming native signal crayfish for commercial purposes; promoting a demand for what some believe to be the crayfish of culinary choice. I understand the Louisiana crayfish farmers commonly farm rice and crayfish together, although at separate harvesting times during the year.
(In sarcastic tone) I’m not sold on the idea of attempting to copy that tactic in the Pacific Northwest! Clark county can be quite cold and I’ve yet to see a rice patty. :-/ That being said, I’ve yet to see a crayfish farmer. But I’ve got the time and the dime. I’d like to see more crayfish etouffee offered in restaurants, craw-boils becoming more mainstream- as well as more people enjoying them as pets because they really are marvelous creatures.
Do you have any information you might want to share or advise as I’m not asking a specific question but just conveying a dream / goal of a simple and sustainable way to hatch, nurture, & harvest crayfish in either an outdoor seasonal environment ( as close to a copy of my Louisiana competitors as possible) or indoors year-round with multiple tanks ( in closed loop systems and what I fear may be higher maintenance with higher cost, yet more environmental control). I also would be keen on growing my own crayfish chow in either senerio; if you had an opinion on a diverse range of plants to grow, with crayfish nutrition and diet balance being the main focus, I’d appreciate your guidance. Thank You!
Robert Brand says
I live in Canada, so farming crayfish outside here really isn’t that viable. I know a few fish farms dedicate ponds to crayfish, but there is nothing on any sort of commercial scale. I’m also aware of a few people who have attempted breeding crayfish indoors, but the finicky and fragile nature of hatchlings made it incredibly difficult to breed them. Also, the sexs had to be separated in grow out tanks, so it’s very labour intensive. I know one of the major problems was they lost huge numbers of hatchlings in the filtration system, and I’m not sure if they ever solved that problem.
I came across this article a while ago, and it gives good information on how to farm Red Claw Crayfish in ponds, which should work with few modifications in North America. http://www.thefishsite.com/articles/1468/cultured-aquatic-species-red-claw-crayfish/ However, I know the reason most people grow crayfish in farming operations, is that it’s hard to turn a profit from just crayfish farming. But I’d love to hear about what you end up setting up.
Robert says
Hello, this site is great info! I do have a question also. I got an dwarf electric blue crawfish for my community tank about 2 weeks ago (I know now probably not the best idea) she hasn’t taken out any fish yet but chases them sometimes if they cross her path. Will keeping the the blue “night” light on at night give the fish a better advantage at survival? Thanks!
Robert Brand says
I don’t think that a nightlight will help with fish survival in a crayfish tank. It would probably mimic the light of the moon, so the fish would still fall asleep with it on. A lot depends on the species of fish, and any species that doesn’t sleep near the bottom will be far safer. You can try to keep your crayfish well fed, which helps somewhat. Also, in my experience the electric blue crayfish aren’t nearly as homicidal to fish as most of the North American species – though they will still catch fish if they can.
Robert says
Thank you for the quick response! I guess I just thought it might help them see her coming with the night light on. But it also may help her see the fish better to attack? I don’t know… I have a 40 gallon bowfront tank with 5 cherry barbs, 2 swordtails, 3 platys, 2 Mollies, 1 rubberlip pleco and 2 mystery snails. Most of them did sleep near the bottom at first, but now it seems that they are starting to sleep closer to the top. Except for the platys who continue to test thier fate and sleep on the bottom still. Thanks!
Sandy Picklesimer says
Hi Robert:
I’m totally mesmerized by this site. I have an electric blue and didn’t know a thing about him until I reached your information. Now I have pertinent info in a file on my laptop. I so appreciate all this info. My question is… is it possible to purchase a crayfish and it have a bacteria that would be detrimental to goldfish? I am such a fanatic about proper water parameters but when I returned from a vacation (shortly after purchase of “Blue”) I believe my goldfish had fin rot and subsequently died. Is it possible for a crayfish to bring something to the tank?
Thanks, Robert. Have a great day.
Robert Brand says
First of all, I’m glad you’re enjoying the site. It’s always great to hear that.
As for the crayfish, I doubt that that it would carry any bacteria with it, though the water from the pet store can often be laden with harmful bacteria and fungus. Never, ever put any of the water from the pet store in an active aquarium.
Usually, fin rot points towards something being wrong with the water. Ammonia and nitrites can both damage a fishes fins, and fin rot will often set in afterwards. Also, if you have a fancy goldfish, it can suffer damage to its fins if the water is very cold, though I doubt it would get cold enough inside of a house – but it could be another culprit depending on where you keep your fish.
Sometimes fin rot develops as a secondary infection too. Were there any other symptoms, like fungus growing on the fish? The loss of fins may have also been from the crayfish. I know I tried an experiment a few years ago where I tried to keep rosy red minnows with a crayfish, and it tore off most of their fins in short order. Since then, I’ve stuck to crayfish only aquariums.
Robert says
I just recently learned the hard way that with an electric blue crayfish they really shouldn’t be with fish. At least the one I have. I had put one in a community tank because my lfs said “she will do great in there”and within a week she had clipped off partial fins of at least 6-8 fish. I ended up buying a separate 29 gallon tank just for her.
Robert Brand says
That’s one thing people usually end learning in the hobby- don’t trust your LFS. And while some people seem adamant that you can safely keep crayfish with fish, all of my experiences point to it being a bad idea. I even had a friend who lost an arowana to crayfish, and he was not happy at all about it. It’s rough that you had so many injured fish, but hopefully they all recovered.
Sandy says
Robert,
I haven’t been pinched yet but, how much does that hurt? And… how do you safely get a cray to let go? I’d like to be prepared for the worse. Also… my blue lost a claw a couple weeks ago. How long does it take to grow back?
Thanks a bunch.
Robert Brand says
Being pinched by a crayfish hurts to a surprising amount, and I always wear gloves when handling mine. Usually, when it pinches onto to something, I just lightly shake it off. It will generally let go pretty quickly, though there have been times where I have to gently pry it off my gloves. But as long as you approach it from behind, you can usually grab it with no issues. I sometimes put one hand in front of it to distract it, and then reach behind it with my other hand.
As for the claw, it usually takes a few molts to grow back to its original size. But you should see a small claw by the end of its next molt.
Sandy says
I’m so glad you’re here Robert,
I’ve found out I have questions even after you answer one… Now I’m wondering if crayfish overeat. Will they eat too much and get too fat/big? And I saw somewhere that peas should be blanched as well as peeled… do all veggies need to be blanched? And what happens if they aren’t?
Thanks for allowing me the opportunity to ask so many “strange” questions. Your website makes if very easy for me to get answers soon. Gives me the feeling of being capable to giving my Blue what he needs and understanding the care he needs.
Sandy.
Robert Brand says
You don’t need to worry about them overeating, but you do need to worry about them hoarding food. They will often hide any excess food, and it will start to rot, which leads to the water becoming fouled. So make sure you search all of the caves during weekly cleanings, and remove any extra food.
As for blanching, the process of boiling them for a short period of time removes any microorganisms that may be on the vegetables, and also makes them more tender for the fish to eat. And in cases like zucchini or cucumber, it will also help them to sink, rather than have them floating around in your aquarium. Though they do take a little longer to blanch than other veggies.
And there are no strange questions – especially with crayfish. They are such unique creatures, and have so much personality that you’re always discovering new things.
Sandy says
Hi Robert,
Can crays tolerate water temperature changes well or do I have to be careful in adjusting the temperature with my crayfish like I do with my fish? Also… I’m looking for a name for mine; got any suggestions? I’ve got a blue and don’t want to call him BLUE.
Thanks.
Sandy
Robert Brand says
Water temperature changes should be kept to a minimum if at all possible. If the change is too fast it can leave them stressed, and more vunerable to becoming ill. And a very sudden change, will usually kill them outright, and studies have shown that any significant temperature change (usually greater than 10 degrees) will kill them in a matter of hours.
As for names, how about Mr. Pinchy? Or Smeagol? Or Fluffy ironically? 😉
Sandy says
Robert,
I just read on a website (http://bluecrayfish.com/north_american_crayfish_care_she.htm) that crays can drown and if the electricity goes off, they should be put in a bucket with limited water etc.etc. How probable is drowning for a cray?
Hope you’re having great weather there in Canada!
Sandy.
Robert Brand says
Theoretically they can drown, but it would have to be a long power outage, and a small aquarium. They have very high oxygen requirements, which is why you need to have an air stone or filter to aerate the water. When the power goes out, the filter will turn off, and oxygen will slowly deplete. If it looks like it will be great than a few hours, I would definitely recommend placing them in an environment where they can get out of the water.
You could also aerate the water yourself with something like a turkey baster, or by stirring it – though it wouldn’t be nearly as effective as a filter.
Sandy says
Another question, Robert:
Are there advantages to putting crays in distilled water or jug drinking water?
Robert Brand says
There are very significant disadvantages to using distilled water for a crayfish, as the water is soft and crayfish need hard water. A crayfish doesn’t do very well in soft water at all, and it will have trouble getting the minerals it needs. Also, it would very likely have trouble with molting, since it would probably develop a calcium deficiency. So always stick to using treated tap or well water.
Tiff says
I add crushed oyster shell to my tank now and then, helps them with molting. Also, I hold my crays by their “saddle”, though my Spector Cray is getting pretty adept at contorting. He has become a lot more submissive when I reach for him. He just kinda tucks his tail under and backs into a corner because he knows I’m coming for him to try to clean the algae off his exo. My blue female? Mean and NO FEAR of me. I think she actually looks forward to me sticking my hand in the tank cuz she comes at me every time.
Sandy says
Thanks for all your info Robert.
Now ANOTHER question…. do I need to peel the cucumber for the cray? AND do they munch eat like eating a corn on the cob, or do they stick a whole piece of food in their mouth and then chew? 🙂
Pretty strange question, eh? I smile wondering just how strange a question I can come up with! 🙂
Sandy
Robert Brand says
Unpeeled is fine, although sometimes they may leave a little ring for you to take out of the tank. But usually they will eat it all. And they tend to tear chunks out of the vegetables, without much in the way of chewing, though it almost looks like they do when they use their maxillipeds (the little graspers in front of their mouth).
Sandy says
Hi Robert:
Me again – How acute are their sight, smell, and hearing? I KNOW, I KNOW, I can get this info from a search engine, but I always seem to get multiple answers and I end up coming here anyway sooooo….
Another smile has hit my lips!
Sandy
Robert Brand says
While their eyes are very different from a mammals, they tend to have very good eyesight, and I’ve read some researchers state it is almost on par with ours. Their ears are very simple though, and mainly exist to detect vibrations in the water. The small antennules above the large antenna are used for smelling, and are used to find mates, and detect predators, while other sensors on their legs are used to detect chemicals in the water (mainly food related signatures). While I don’t recall any studies testing their sense of smell, I do recall that nearly half of their brain is dedicating to processing their sense of smell, whereas humans only use something in the neighbourhood of one percent. So I would hazard a guess that their sense of smell is exceptionally good.
I hope this helps. 🙂
Sandy says
This is great info. I never would have guessed they had sensors on their legs. I was just wondering if mine could detect when I put something in the tank for him to eat. He always seems to start hunting around shortly afterwards. And I was wondering if they detected vibrations as I always call his name pretty loudly before I put his food in. He’s still wanting to hide after he grabs his food. He’s the only one in the 20 gal and it’s only me and my hubby around the tank and I’m wanting him to be out more. I’ve only had him for a month and I know he’ll come around when he’s ready, he’s just not ready soon enough for me. My last cray was a little more adventuresome.
Thanks, Robert. You’re an angel!
Sandy
Vighnesh Alungal says
i need serious help i bought these 2 crawfish ( i just love crawfish) the 2nd day a portion of my comets tail is gone. i researched on how to fix it but got know clue expet for the idea of clipping since im new to crawfish i dnt want to take risks so can anyone help me with this situation it would really make me happy.
Robert Brand says
I, personally, would never recommend clipping. It’s cruel to the crayfish, and only a temporary solution. The only thing you can do in this situation is rehome either the crayfish or the goldfish. Until you can do that though, you could also put a divider in the tank to keep the seperated. Other than that, there’s nothing you can do.
Sandy says
Robert,
I guess everyone else has their questions answered, as I seem to get more questions!
I was cleaning out the tank and found the cave a little slimy so I scrubbed it clean. Afterwards I started wondering if the slickness is a good thing for my cray. What do you suggest? To clean or not to clean… that is the question.
Thanks a bunch.
Sandy
Robert Brand says
You should be fine cleaning it off, as it’s normally algae or bacterial growth. The removal of either really won’t affect crayfish and you should be safe doing it. Just avoid using untreated tap water or anything else that could affect your aquarium while cleaning it though.
Hope this helps.
Sandy says
I never associated using untreated water to clean as detrimental to my crayfish. When I say “clean”, I mean taking the cave out of the tank and washing it off. Does the resin/plastic absorb that much water to be harmful?
Robert Brand says
It wouldn’t absorb very much to be honest, but I try to keep any chlorine out of the water. While it would probably only be added to the aquarium in tiny quantities, I still tend to err on the side of caution. But I’m also a little on the extreme side when it comes to that, so you could probably continue to do that.
Sandy says
I like to be over-cautious as well…. my lidl baby’s life is at stake. Great info Robert. I really appreciate all this stuff.
Robert Brand says
I’m always glad to help out. 🙂
Nikki says
My brown cray fish had babies a few weeks ago and we woke up today and she has died. I have a very small tank. Under a 5gallon so please tell me what can i do to keep them alive. Any advice is so appreciated. I will change the water today. Im scared it was the water quality or perhaps the tank got too small? I wish i knew why she died. Thanks
Robert Brand says
It will be tough to keep them alive. While size is a bit of an issue, the bigger problem is the rampant cannibalism that will occur. As they grow, they will continually eat each other. But you can try to give them as many hiding places as possible, and keep on top of water changes. Without rehoming them too aquariums as they grow, there’s not much else you can do.
Mindy says
If a Florida brown crayfish mates with an electric blue crayfish, what color will the babies be? Will they be a mixture?
Robert says
Hey Robert, my blue cray has a white fur like something on her face and claws. Has had it for at least a couple months. She acts normal and it doesn’t seem to bother her. Should I be worried? Thanks!
Robert Brand says
Do you have any pictures? Sometimes it’s normal (but only when it’s barely noticeable), but most of the time it’s either a parasite or fungus. If you can e-mail me at admin@aquariumtidings.com, I can give you a better idea of what to do.
Robert says
Sent a pic.
JSigmo says
This is a good article about crayfish. It’s the first one I’ve found that recommends the sinking shrimp pellets, and those are one of the few commercial foods we’ve ever had success with. Crays and fish all love ’em.
But the main things our freshwater crays seem to love are earthworms and, of course, fish. All of our crayfish were caught in our presedimentation basin (for a water treatment plant) or raised from babies. We also have an enormous population of minnows in the basin, and many get past the pumps and make it into the water plant filters. So we keep quite a few in with the crayfish.
The crayfish love to eat the minnows when they can catch them, but the minnows are quite adept at avoiding being caught. The minnows even “hide” right under the crayfish when they’re scared. It’s kind of strange, but interesting.
Often, minnows are killed as they pass through the pumps feeding the plant. We scoop them out of the filters and feed them to the crayfish. They love ’em!
But I never seem to see earthworms (night crawlers, or red wigglers, etc.) mentioned as crayfish food. Yet these seem to be the absolute favorite for all of the crayfish we’ve ever had. They go nuts for them. They get so used to being fed the worms that they come right over to one’s hand or anything we stick down into the water. We have to shoo them away when vacuuming the tank gravel or sand in the aquaria to avoid injuring them. They just know they’re going to be fed, and run right up to the vacuum pipe!
We’ve never had any success breeding them in captivity, though. They mate frequently, but no eggs are ever produced. I believe this is because the species we have need to be kept very cold (simulating winter here), and then produce eggs when the water warms up in the spring. We could try chilling the water for a few months, and then letting it warm up to simulate this, but have not tried that.
But, we can easily catch females already laden with fertilized eggs out of the basin, so that’s where we’ve ended up with baby crayfish.
They truly are interesting and fun aquatic pets.
Initially, I put a few into a new 55 gallon tank to provide the ammonia to get that new tank’s nitrogen cycle started. But we all grew so attached to them that the tank ended up being a crayfish tank. Then we set up another 55 for crayfish, and now we need to get another one set up because we’ve got a mamma crayfish loaded with eggs that are fairly far along, and we need a nursery tank just for the babies once they swim free of her.
Anyhow, if you haven’t tried it, get some earthworms and see if your crayfish don’t go nuts over them!
Robert Brand says
I often feed nightcrawlers and red wigglers to my fish, but I’ve never tried them with crayfish. It’s a good idea though, and I probably should have thought of it a while ago. My only fear would be that the crayfish would hide the earthworms for a snack later, and something that size would really do a number on the water quality. Have you found any hoards of earthworms when you clean your aquarium?
And I’ve had many tanks magically ‘morph’ into crayfish tanks. They’re addictive when you start keeping them, and they always give you great stories to tell friends and co-workers.
Leanna Megan says
My electric blue lobster is starting to act weird. He’s going up to the top of the tank using the fake plant and laying on his side while holding onto the plant. If I look at him he becomes real shy and runs to his log but after 5 minutes of me leaving he’s back up again. What is wrong with him?
Robert Brand says
Unless he looks ill, I wouldn’t characterize this as odd behavior. Mine would often climb the air hose line, or the fake plants, in an effort to escape their aquarium. They tend to be very curious animals, and enjoy exploring their aquarium. During one of my ill fated attempts at keeping crayfish and fish together, mine would spend much of his day at the top of the plants, trying to catch fish as they swam by.
So unless he appears ill, has any growths or discolorations, I wouldn’t worry too much about it.
Leanna Megan says
It was his way of letting me know that something was wrong with the filter. My snail layed it’s eggs in the filter and blocked the tube from filtering the water.
Robert Brand says
No, I wouldn’t worry. Snails aren’t the most intelligent creatures, and they lay eggs in the oddest locations.
Leanna Curry Gores says
I’m back again. My electric blue is on his side and not moving even his tail is curled up but about 30 minutes ago he was running around the tank like normal. my boyfriend thinks he’s dead what do I do?
Robert Brand says
It could be molting. I would give it some time and see what happens. It’s rare for it to fall ill so quickly.
Leanna Megan says
It’s still not moving and now my shrimp have gathered around it and started picking at it. It just molted for the second time this month about t days to a week ago.
Leanna Curry Gores says
I’m guessing it is dead. I left it in a net over night because I did not want my other fish to bother it and it turned pink under the shell and hasn’t moved.
Tiff says
Story #1
I have an electric blue female lobster and a white male lobster. The male was so aggressive when I first bought them that he accidentally lopped off both pinchers and feeding claws plus 6 out of 8 legs from my female blue during breeding. She was a pitiful mess. I thought for sure she would die, but I moved her to another tank in hopes of healing her(I’m a Wound Nurse by trade). I increased the calcium level in the tank, made sure I put sinking pellets in a pile in front of her(she had nothing to hold her food with), and hoped for the best. After two molts she had all her legs and pinchers back, and was considerably larger than the male. Problem is, I initially put her in a tank with my orange dwarf cray. She was no threat to the dwarf because she had no pinchers. After the second molt? No orange dwarf cray. Not a leg, not a claw, no NOTHIN. Blu ate her I’m guessing. So I moved Blu back in with the male, and he’s breeding her like crazy. I hope he doesn’t dismember her again(?).
Story#2
My white male lets algae grow on him. So every now and then I take him out and scrub him with a tooth brush(picture that for a minute, it’s pretty comical). Needless to say I can’t get every bit of algae off of him so I put them back in the tank. I noticed that every time I do that he will start rapidly cleaning himself probably thinking that if he doesn’t clean himself the giant lady with the big toothbrush will clean him. I’ve had him a year and he’s only molted twice, or else I wouldn’t be force cleaning him 😉
Story#3
My orange dwarf cray was a female(Blu ate her).
I LOVED that little girl. I gave her 3, count em, 3, male dwarf crays on three separate occasions, and each time, after a couple days, I’d find the males literally cut in half at the tail/saddle segment. Guess she didn’t want a boyfriend lol!
Robert Brand says
lol…that sounds like a dangerous dwarf crayfish. A black widow crayfish?
But this is one of the reasons I like crayfish so much. They have so much personality, and they’re always giving you great stories.
Willie says
Hi. a while back I wrote about my blue cray not eating pellets after it molted a 2nd time. I had purchased 5 small gold fish to see if he tries going for them and instead they became friends. He never chased them and they swim around the cray without fear and even hang out in his barrel with him to sleep.
Months has passed and three of the five gold fish are tiny (I guess that’s their breed) the other two are just as big as the cray. I’m changing water and filter like you don’t believe and don’t know what to do with those two large gold fishes. Not sure how long the cray can go without food, I see the fish attacking the pellets when I throw them in but hardly ever see the cray eating and like I said, it’s been months. I don’t need another tank for I have another 15 gallon with 4 small freshwater fish in them that I can’t put together with the cray or gold fish.
Would a pet shop that sells fish, take grown fish? I think I need to return them to where I purchased them. They did not surve their purpose and only making me spend more money on filters. Currently the cray, 3 small and 2 large fishes are bunking in a 10 gallon. Kind of reminds me of my college dorm, without the water. I know how crowded and uncomfortable it can be. I’m expecting to see the larger fish going after the smaller ones for food if I don’t do something soon.
Robert Brand says
Most fish stores excluding the large chains will take fish back. They often won’t give you any money for them, but depending the species (most livebearers aren’t wanted), they will take the fish off of your hands and resell them. You could also try local fish forums or craigslist. You’d be surprised how many people are giving away fish on those sites.
Tiff says
Goldfish create a HUGE bioload in a tank at a very fast rate(meaning they create too much waste) I always get guppies. They are small and won’t eat much. Though my crays are spoiled and won’t eat the guppies, but rest assure, your cray IS eating, probably from a hoarded stash of food.
pidgeroo says
I’m trying to reply to Tiff’s tale of the algae covered White. My orange cray always got algae on her for a week before she shed. I wondered if it had something to do with the separation process. Did you notice this at all?
Tiff71 says
No I didn’t notice this. He’s been steadily growing algae on him for about six months and he has not shed during this time:)
kari says
Hi,
I’ve been looking for some information as to what may be going on with my blue cray. Lately she has been excessively cleaning her tail. We’ve had her almost a year, recently we have moved her into a new tank(it is a 40 gal that was set up with a few Molly’s for about three weeks before the cray was put in). She has been eating the plants but is now refusing algae disks and shrimp pellets. She has started laying on her side out in the open. Previously before molting she would hide and lay on her side. She is still responsive, she has gotten a little slower with this new laying out.
I’m mainly worried that this new behavior may be a bad sign. Any ideas?
Thanks for your time!
Robert Brand says
It sounds like it’s having trouble with it’s molt, but it might also be ill. First things first, check all the parameters of the tank. Make sure nothing is out of whack, and if everything is fine, then take a good look at the crayfish. Does anything look out of the normal? Most illnesses are hard to see, but sometimes you can see some issues.
Beyond that, there’s not much you can do, but leave your crayfish alone. If you bother it too much and it’s a bad molt, it could stress it out and make things worse. I wish there was more that I knew to do, but it’s hard to treat crayfish with an illness.
Cole says
I have a 2 gallon tank and about 20 babies in there…this isn’t gonna end well
Robert Brand says
Probably not. It’s going to be like an all crayfish version of the movie ‘Alive.’
Eric Messenger says
This thread is crazy long, I only read about half of it but I wanted to comment on my experience with crayfish and aquariums in general. Those who have said that the crayfish or the fish will eventually get eaten are correct. When I had large Oscars and Red Devils in my 55 gallon we would go to local shallow rivers and catch crayfish as feeders. I’ve seen a 10″ Oscar suck up a 4-5 inch crayfish, chomp it up, and spit out the pincers. We also fed our large Cichlids goldfish feeders; the crayfish would catch and eat the goldfish as well. I just recently started over with small cichlids after my thermometer broke and literally cooked all of our large fish. We just went to the river today to catch some crayfish for the tank; the kids love having them. So far there is just a lot of fighting between the aggressive cichlids and the aggressive crayfish. Neither seem to be doing any damage to the other since they are all 4 inches or less in length. So, maybe the answer is to let community (wimpy) fish have their own tank and if you want crayfish and fish in the same tank go with some sort of African or Central American cichlid that is aggressive enough to hold its own. If you want your crayfish to survive, I would recommend not putting them in a tank with Oscars. Oscars grow faster than any fish I’ve ever had and open their mouths extremely wide relative to other cichlids. After a year or so the baby Oscar you bought will be swallowing 3-4 inch crayfish whole.
Keamen says
What does it mean when the crayfish only had eggs for 7 days and is scattering them all over the tank?
Keamen says
by the way it is an Australian Red Crayfish if this helps
Robert Brand says
It probably means that the eggs weren’t fertile. Otherwise, all of the species that I know would hold onto them. You’ll know for sure when she starts to consume them.
Keamen says
I don’t know for sure but someone else said it was because the water was dirty.
Karen says
I’ve been babysitting a crayfish for three weeks and was instructed to feed him (Jerry) 3 shrimp pellets a day. I have noticed that he appears to be ravenous everytime I feed him and devours the pellet instantaneously. He’s a good size in a 10 gallon aquarium. I don’t want to change his intake of food unless I discuss this with his owner(s). Any suggestions?
Robert Brand says
A good rule of thumb is to feed how much they can eat in a few minutes, once or twice a day. I would say a full grown crayfish might need to eat more than just three pellets a days – depending on the size of course. But they are omnivores, and I’ve seen ones that can seem to eat their whole body weight (I made the mistake of putting a crayfish into a planted aquarium once).
But I would speak to the owners first, although I’m sure they wouldn’t mind if you gave it some treats like lightly boiled zucchini or bloodworms. 😉
pidgeroo says
Our orange crayfish died this week 🙁
The water temperature was 82 degrees because we’re in the middle of Ontario summer with no air conditioning here. Do you think the heat might have caused her death? We have the tank away from sunlight etc with LED lights in it and there is little else we can do to keep it cooler. Is there a crayfish breed that would tolerate this temperature more easily?
Also, are you near Toronto at all? We’re hoping to buy a replacement from someone knowledgable.
Robert Brand says
Depending on the species, that is definitely at the outside range of what a crayfish can tolerate. There are a few tricks you can use to keep it cool in the hot, muggy Ontario summer (yes, I’m from Ontario too.) The first is to keep the blinds closed in the room, which will keep the temp down. Then you can position a fan to blow on the surface of the tank, which will also help to lower the water temp. Finally, you can rig up something over the tank with a hole in the bottom – like a old rubbermaid container – and fill it with ice. As it melts, cold water will drip into the tank slowly.
As for breeders, they tend to be few and far between for crayfish. Many of the good ones I’ve found have been on forums for Toronto (though this is getting less common), or through adds on kijiji. I also like to capture my own through traps, though I can’t say if that’s illegal or not. Especially if you’re transporting them ,then I’m pretty sure you could get in big trouble. But I tend to only do it close to home where that likely won’t come up. You can also do special orders through Big Al’s sometimes, and you can get some really interesting ones there sometimes. Though usually you’ll need to find a few people to go in with for a a minimum order size. But they aren’t always in the best shape after traveling here though, so a word of warning on that one.
pidgeroo says
Thanks! Some great ideas 🙂 but my husband will object to them aesthitically! Is there a good site (apart from this one!) that would show which breeds would tolerate the warmer temperatures?
Robert says
I have a male blue Australian red claw. They are from very warm parts in, you guessed it, Australia. Lol, my tank ranges from 78-82 and he does great! They do get on the bigger side, 7-10″, so a larger tank is needed. Very cool species, males get bright red/orange lower claws.
pidgeroo says
Wow, that sounds beautiful and would certainly be aesthetic! I’m not sure our twenty gallon would suit him though – I might need to buy a bigger tank! This habit could work out more expensive than getting air conditioning!!
Robert Brand says
They methods sure are not attractive, and I can understand that.
There are some breeds that can survive higher temperatures, the problem is finding them for sale. Maybe the only ones regularly available are yabbys, or Australian crayfish. They can survive at the temps you describe, but you don’t want to keep them at that long term. I’ve never kept them, but I’ve heard Hammers Cobalt Blue Lobster also do well in hot water. Beyond that, I can’t think of any other available crayfish for high temperatures.
Kima Caddell says
Hey there. My blue freshwater crawfish has had a bad molt. One of her claws is gone, and the arm that it should be attached to seems long. The other has a brown shell? on it. I have a photo, don’t know how to share here. Appreciate any help or suggestions. Baby Blue and I thank you for this forum. Kima
Kima Caddell says
I posted photos to the Facebook page. Hope that is cool. Kima
Robert Brand says
I took a look at the picture, and I’ve never seen a growth like that. I’ve seen smaller, somewhat similar ones from fungus, so I’d probably assume it’s related. The best way to treat fungus is to really focus on your water quality and to supplement the iodine through either cuttle bone, or low strength marine iodine supplment. The next molt should get rid of the problem that way then.
As for the water, do you have a filter? How large is the tank? How often do you change the water?
Kima Caddell says
Thanks for your time. Blue has a 20 gal long tank.. Hanging fluval filter, rated for a 40-70 gal tank.. Water changes every 3 weeks. Overdue now for 1 week as I didn’t want to stress her after this molt went badly.. I do add kent marine iodide, a few drops every few weeks. Blue is fed daily 3 aqueon shrimp pellets and a tetraveggie algae wafer every other day.. Tank has 1 minnow, 7 small tetras (neon and another simular species with red marking).. And a small under 1.5 in pleco. Temp is 73.3F.. Did change filter substrate aweek or so ago, since I didn’t want to change water while she was struggling.. Last three days shehasbegun acting mire normal, active, climbing.
Kima Caddell says
I feel really bad, guilty, I startled her during her molt, trying to lessen a vibration at back outside of tank, (have two bubble stones in tank and pump was rattling against glass) she freaked out and jumped out of old skin, except for messed up claws, so i’m afraid I caused most of the damage… We have 5 active tanks, most wit just fish, but we do have a freshwater turtle.. We are pretty serious about water quality.. I usually would provide water quality data, but loaned test kit to a friend who kept getting ick because of not doing water changes.. Was planning on a water change tomorrow since she seems to be improving. Feel like crap that she’s not 100%.
Kima Caddell says
Me again, Rob.. Went to get my test kit. You are right- water quality is the issue. Ammonia is .25, high range ph ( MT has alkaline water) 8.2,nitrate 0ppm, but my nitrate is THRU THE ROOF! Above 80 ppm. Oph. I’ll get on the water changes and since it’s so high will probably do 15% changes daily until I get it down. My husband thinks I’m overfeeding her- do you recommend every other day? We had stocked more fish this go round, and she dispatched 8 small neon tetra/glolight tetras- maybe she buried instead of eating? That might have also contributed to the extreme nitrate level. Thanks for your help. Shame on me.
Robert Brand says
It’s good you seem to have located the issue though, but I would stick with feeding every day. Just trying to lessen the amount of food you’re giving the crayfish, so that’s it all within about two minutes.
And my bet is that you have rotting fish somewhere in the aquarium, since crayfish are notorious for hiding food for later – and then forgetting about it. I’d search every decoration and cave, as well as looking through all the plants and substrate. Once you have the situation under control again, the crayfish will hopefully return to good heath again.
Good luck.
Kima Caddell says
Thanks tons Rob. I really appreciate this thread. I’ve bought books on crayfish, but our lps really doesn’t know anymore than I do….or so it seems. Thanks for being a resource!!
Robert Brand says
I’m always glad to help.
Keamen says
Is there anything wrong with by Äustralian Red Crawfish because they are each eating around 10-20 frozen garden peas a day and they are only slightly over 5 inches?
Robert Brand says
Why do you think something is wrong with them? How old are they? But, I will say they would probably appreciate a more varied diet though.
Keamen says
I think something is wrong because each day they are eating more and more and now their eating nearly as much as their own body-weight. What other foods do you think I should get for my crawfish that I can find easily because the crawfish are just ignoring the carrots and corn.
Keamen says
By the way I don’t know how old they are because this is my first lot of crawfish and I bought them from a shop.
Robert Brand says
So why do you think something is wrong? The only thing I think you should do is try other foods. It doesn’t sound like there is anything wrong to me.
Melissa says
We caught a non-native crayfish in camp and did not want to release back into the wild so we kept it for education programs. It (have not sexed it yet) is doing well in its tank for many weeks now. We would like to use it during educational programs off site. What is the best way to transport a crayfish. We have turtles and snakes that travel in the plastic container from pet stores. Would this work? Also do they need to be put into water at all times? I read other places that they are shipped live out of water for a very long period of time, is this okay?
In the cooler months it will travel in a cooler as well to avoid drastic temperature changes.
Thank you!
Robert Brand says
They can be transported outside of water for fairly long periods of time. But how long are you talking? The key is to keep the humidity up so their gills don’t dry out. This can be accomplished by putting a small amount of water in a container, or even wetting something like a paper towel, and placing it in there with them. Make sure to place them in water just below their gills first when you’re ready to put the crayfish back into the aquarium. They need some time to get used to water again before they’re placed in an aquarium.
Also, put them in upside down, so any bubbles on the gills are dislodged when you’re adding them.
usagrammy says
Hi Robert, well Harriet, my blue lobster had 4 or 5 babies. not sure as they’re so good at hiding. 3 days ago I counted 5 all different sizes and yesterday I only saw one. today I’ve seen three. I’ve been reading all the comments to gain knowledge so thanks everyone. Harriet and her fry have eaten ALL my plants, so I’m gonna try a frozen brussell sprout and zuchini tonight.
Robert Brand says
I had the same experience with my plants when I first started keeping them. I was shocked my crayfish could devour an aquarium’s worth of plants in no time flat.
But you’re obviously doing something right if the fry are surviving, and hopefully you’ll be able to grow them into full-sized adults. The addition of vegetables is a great way to give them more nutrients, and you should also consider adding some cuttlebone or marine iodine supplement (no more than half strength) since the fry molt so often.
Also, be careful to check all of the hiding places during the weekly cleaning. Crayfish love to hide vegetables to eat later, and they quickly rot, which fouls the water.
Tkellett says
I have 3 procambarus alleni crayfish can I put a procambarus clarkii in the tank with them. I read only put same species crayfish in the same tank. Are these close enough of the same species. Mine are native of Louisiana and the clarkii is native of Florida.
Robert Brand says
That advice really only applies to crayfish from other continents. Generally speaking, crayfish from other continents carry different diseases, and North American ones are known to carry a very virulent strain of fungus that will wipe out crayfish from other continents.
Also, people try to avoid mixing crayfish to prevent cross breeding, though that’s less of a concern for a hobbyist.
So you should be fine with your crayfish choices as long as you provide them enough space.
Tkellett says
Thank you, you are so helpful. How much marine iodine should I add to the water and how often. what should my calcium levels be for optimal nutrition.
Robert Brand says
I wouldn’t go anywhere past half of what they recommend, and just to be safe, I’d even go a little less.
As for calcium, what type of water do you have? You generally don’t have to worry about that if you moderately hard water, and you’re feeding them a vegetable rich diet.
Tiff71 says
Hi Robert!
I have a male Phantom crayfish. I’ve had him for a year and a half. He has not molted in at least a year. Is this normal? Or should I be concerned? He’s in a 20 gallon with a few feeder guppies.
Thanks!
Tiff
P.S. He’s the one that I will occasionally scrub with a toothbrush because he gets ALOT of algae growth on his exo.
Robert Brand says
How large is the crayfish, and what type of water do you have? Their molting slows as they get older, and it’s often influenced by water type and diet. If you feed them a calcium rich diet, as well as ensuring they aren’t in soft water, they should molt regularly. You may also want to try supplementing iodine as well.
Keamen says
Hello, how would you recommend taking care of around 50 newborn crayfish because I can barely see them when I put them in a glass tank.
Robert Brand says
It’s tough when they’re that small. I usually recommend feeding he vegetables like blanched lettuce, and then trying to sort by size. As they grow, I sort out the larger ones and transfer them to new tanks. If you don’t do that, you will end up with a lot cannibalism.
Tkellett says
If I add a few sea shells to my crayfish tank will they continue to add calcium to the water
Tami says
Hi! My question has to deal with the recent find of 3 new young cray fish in my 60 gal freshwater tank.
Background – we have had our electric blue crayfish since late December 2015/Early Jan 2016 and purchased our brown marbled crayfish mid year around June/July 2016 this year….
I’m worried that having now 5 crayfish in our tank (especially when the young become adults) that there will be too many & that they will turn more aggressive towards the community fish that our housed in the same tank.
Next worry is that I will continue to find more crayfish! (they also seem to be thriving and growing rather quickly in size)
Does anyone know where I can donate and transport these young crayfish in the most humane way possible? Or how to control the situation?
Advice welcomed please!
Robert Brand says
Whereabouts are you located, Tami?
Troy says
I have a red crayfish, a white one and a blue one. Now I have about 22 babies now. I do not know what color they will turn out to be. What is the best way to take care of them and how do I get rid of them?
Robert Brand says
The hardest thing about raising crayfish hatchlings is that they are cannibalistic. As they grow, you’ll need to separate them out based by size, and many of them will fall prey to the larger crayfish in the tank. But you can feed them by feeding blanched lettuce or cabbage leafs. It will also help to have lots of hiding places for them, like caves, or small, unpainted clay pots on their side.
As for getting rid of them, you can sometimes give them to local fish stores, or you can post them on local websites. I know there’s a local forum I use for unwanted fish, and with a bit of searching, you can probably find one too.
Dava V Peters says
So I was given a crawfish back in June. Two days ago I thought it died because of the shedding since I did not do enough research when I went to take him out yesterday I then found out it was alive and had babies, 4 so far. I was unaware that it was a female and unaware that it had eggs as well. Everything I am reading says it takes weeks till the eggs detach & turn into actual crawfish but mine apparently it took 4 months is that normal? and should I be expecting more than 4? My tank is only 5 gallons since I only had intended to have one average size crawfish. I’m hoping I can get rid of the babies because I don’t want them killing each other but how long do I need to wait or how soon should I remove them to avoid the mother or the other ones from killing each other.
Robert Brand says
Quite a few factors can influence how long it holds onto the eggs, but four months does seem rather long. But since it worked out alright, I wouldn’t worry about it too much.
As for the crayfish hatchlings, it’s hard to keep them alive in even large tanks. The only way to do it is to seperate them out by size. Otherwise, they’ll resort to cannibalism, even if there are a lot of places to hide. As they grow, you’ll continually need to thin their numbers by removing the larger ones, and it can quickly become overwhelming. But if you have someone to take them, then it’s a good way to make most of them survive.
Omar says
I just found eggs under my Electric Blue Crayfish’s tail. I am preparing a 6 Gallon tank with a filter, air pump, and light. I was wondering what you would recommend I do in properly caring for the upcoming conception in a few weeks. Should I take the mother out of the tank? What should I feed the crayfish when they are born? Should I have hiding places in the new tank or not? I have heard that they might be cannibalistic when they are babies, but the amount of hiding places can either make them more cannibalistic or less cannibalistic. HELP PLEASE!
Robert Brand says
You can take the mother out of the tank, but it’s only a good idea if you already have the new tank cycled. It is much better to have a tank for them alone, and you might be able to use a planted tank to help counteract the lack of cycling – though only puts the babies in, as the mother will eat all of the plants quickly.
As for the hatchlings, you can feed them blanched vegetables like lettuce, or other zucchini medallions. I find more hiding spots reduces cannibalism, but you also need to sort them by size, or the larger ones will eat the smaller ones. Unless you have numerous tanks, you’re going to lose a lot of them.
Omar says
You’re a saint. Thanks dude, also what temperature is best for newborns?
Omar says
Recommended temperature for new born crayfish? Also, would crushed flake food or carrots be okay for the baby crays?
Omar says
So I had a bunch of crayfish eggs under my crayfish’s tail (About 100 eggs). But today as I went to put her in another tank, she only had about 7 eggs. What could have happened to the eggs? I have two red claw crabs in the aquarium and one other crayfish, no fish.
Robert Brand says
The eggs were probably infertile and were most likely dropped and then consumed by her. What color are the eggs?
George says
I have a question I really hope someone can answer. I had two electric blue crayfish living in the same 20 gallon tank. When we first put them in together the male only had one claw. There are multiple hiding places around the tank and the two crayfish seemed to be getting along just fine, they both walked around the tank hunting the feeder guppies and exploring. By the time the male grew its second claw back its other one had grown so big it looked funny. We noticed the female started staying hidden in her hole for most of the day instead of walking around freely. Then one morning i turned the tank light on and noticed they were mating. I’ve tried to research their mating habits so we could have babies and the websites didn’t mention removing the female until there were eggs under her tail. A couple days went by and no eggs so we were worried we interrupted them mating. The next morning I saw them mating again and hoped we were finally going to see some eggs. But then the very next morning I turned the tank light on again and noticed that the female was dead. She was completely intact, no claws, legs, or anything else missing and the pH, ammonia, and everything else was just how it was supposed to be. Both the female and the male were about the same size, except for the claws obviously, but had not yet matured to there full size so it’s not like she died of old age. If anyone could please help me figure out why she might have died I would greatly appreciate it so I can keep this from happening again.
Robert Brand says
Are you certain they were mating and not fighting? Also, what was the temperature? I’ve seen sudden crayfish deaths if the temperature is too high. And how does your heater look? Does it look alright?
George says
ive seen pictures of crayfish mating and the male was on top of the female (kind of a missionary position) holding her claws and thats exactly what they were doing. the tanks only at about 75 degrees and the heater looks normal.
Robert Brand says
Unfortunately, it’s sometimes difficult to determine why a crayfish died. When they appear healthy, it’s often a bacterial infection, or possibly even some hereditary defect. Sometimes you just can’t know.
lexi harris says
Hi hi I have a crawdad that is close to hatching its eggs it lives with a parrot head ciclid and a albino. Oscar but there small will they eat the hatchlings if so what should I do should I put them in a whole different tank and wait till the eggs hatch or use a mesh devider its a 5 gallon tank and I put about a dozen minnows in the tank every week for the predatory fish will the minnows harm/attack the baby’s
Thanks and sorry for so many questions ☺
Robert Brand says
They will definitely eat any hatchlings they can find, and if you don’t have enough hiding places, they will even eat the crayfish during molting. A mesh divider might work, but you generally need a large tank if you want a lot of the crayfish hatchlings to survive. They’re very cannibalistic, and in small tanks, you may only end up with one of two very fat crayfish by the end. Although, you could separate them as the mature, and return some to the larger tank, which may work for a while.
Alex Kooba says
Hi, I am planning on getting a crayfish and I wondering how many times a day you feed it and how much food do you feed it?
Robert Brand says
Once or twice a day should be fine. One good meal is usually enough, but you need to make sure not to overfeed, or it will horde the food somewhere in the tank. Needless to say, this isn’t good the water quality.
Sambabyskys says
I wana know izit female crayfish wont have eggs if they haven mating? And now my crayfish have eggs izit i need to seperate she to ownself a tank and what water tempereture the best to help eggs hatch?
Robert Brand says
Do you know what species it is? Most require a male to reproduce, though I believe a few species can store sperm for a while. Most likely the eggs haven’t been fertilized.
Lindsay says
Hope I put this question in the right place…so I have just set up my aquarium for my crayfish, I put a couple of rock type things for it to hide in…the openings don’t seem big enough…what kind of “cave” do u recommend?
Robert Brand says
If you’re looking for a cheap cave, plain clay pots work on their sides work great in aquariums. Also, you can make a cave out of a PVC pipe if you want to put a bit more effort in. Saw the PVC pipe in half, and then glue gravel or sand to the top of it using aquarium safe sealant. Once it’s dry, you can add it to the aquarium, and they really look amazing.
Or if you don’t like those ideas, you can create a cave out of river rocks – but make sure to clean them thoroughly first, and glue them in place so they don’t get knocked over and break the aquarium glass.
Johncrez28911 says
I have a blue crayfish or lobster I recently put him in a 55 gallon tank. Since I have moved him he hasn’t been eating the shrimp pellets or the wafers. When I put them in the water he used to run right to them and start eating now he doesn’t move at all during feeding. I’ve read that they like vegetables so I figure she would eat wafers because they are made with zucchini he doesn’t even touch him he walks over the food stops then keeps going. I’ve been having this problem for about 4-5 days. I have read that they eat frozen fish song for my question. I was wondering if I would be able to cut small pieces of either bunker or mackerel and see if he would eat that yes I do know that those are saltwater fish and he’s in a freshwater aquarium so that is why it’s a question. I was wondering if not those two fish is frozen shiners/minnows would be better.
Robert Brand says
It’s actually much better to feed them saltwater fish, as they usually won’t carry and diseases or parasites that can affect freshwater tank inhabitants.
But as for the crayfish, it might be preparing to molt. Or it might have been a pretty big shock to it’s system switching tanks. Keep trying to feed it, but remove any uneaten food from the tank afterwards, so the water doesn’t foul. Beyond that, all you can really do is keep the water clean, and keep trying to offer food. I know many of them really like frozen foods like bloodworms or brine shrimp, so those might be worth trying as well.
Let me know how the crayfish does, or if anything changes. I might be able to help.
Johncrez28911 says
OK thanks I believe he starting molt he’s been picking at his body since last night last time I think he ate was Sunday morning before I left for work but I know A few days before that he ate two of six go shrimp so I’m hoping he’s just in a slower molting process
Leonard Matyjasik says
Hi,
I have a 55 gal. tank with guppies and 3 small blue shrimp 5 ghost shrimp and 3 orange cpo’s. I am totally surprised that my orange crayfish are calm around the the small fry and I think they know they’re babies and even remain still and let them swim all around them. But when a adult comes around its claws up and they know better to swim away. Even further I tap on the tank in a particular pattern to signal the guppies its feeding time and a male cpo I had the longest has caught on to this and comes out on cue to eat its the cutest thing. I have a female with eggs and wondering if it would be wise to put her in a breeding net that can be suspended on the top of the tank? I would put a lot of stringing live plants in with it or just leave them alone. I have java moss and lots of thick artificial plants some fake corral and 1 real corral. Can send a pic of the tank.
Robert Brand says
I’d probably go with a net if you want a significant number of babies to survive. Otherwise, even with the plants, you’ll still probably lose a lot of them.
Robert says
Hello, I have an Australian Red claw (cherax quad). He is about 7-8″. How much should I be feeding him? Right now I give him either 8-10 little crab cuisine pellets, 2 algae wafers, 5-6 blanched peas, 2 zucchini slices or 2-3 frozen krill once a day. Is that enough? Thanks!
Robert Brand says
That is a lot of food for a crayfish. Does he eat it all in one sitting? Crayfish that size usually eat far less than that. A good rule of thumb is to only feed as much as they can eat immediately. There should be none left over by the time they’re done feeding.
Robert says
Yea he eats it right up. Sometimes takes him a bit on the peas and zucchini, but he is continuously eating until it’s gone.
Robert Brand says
Is the water quality alright in the tank? I would probably ease back on the feeding for now. Maybe ease a back a little and see how it goes. Crayfish are gluttons and eat relentlessly. I made the mistake of planting my first crayfish tank, and he ate every plant in the tank overnight. For now, I’d stick with as much as they can eat in 5 minutes.
Nadia Wood says
How many can I keep in a 20 gallon tank
Robert Brand says
If you place a lot of caves and hiding places, you might be able to get away with three at the max. But you’re probably pushing your luck with that. Two would probably be ideal in a tank that size.
Jocelynn Cruz says
Hi! So, me and my brothers found a crawfish (mudbug whatever you wanna call it) in our pasture. It’s the kinda that burrows in mud? I’m not sure what it’s exactly called. Um, so apparently that crawfish, was a mamma. So when we didn’t know, we put it in a bucket. And then a little bit later found she had a bunch of eggs under her tail. The bucket isn’t currently filled with mud (seeing as that’s the habitat we found it in) and a little bit of water, what would I need to do to her? Would I still need to put it in a waterish tank? Or because since she was found in mud, does she need mud in it? And I’m sure she eats all the stuff the other crawfish do right?
Jocelynn Cruz says
IS currently filled with mud. Sorry, autocorrect.
Robert Brand says
Whereabouts do you live? There are numerous species of crayfish, and I don’t have experience with them all, but working with mud can be quite difficult. Most crayfish will thrive in a tank with stones or gravel at the bottom, and it’s far easier to keep clean than mud. Also, they will need something to aerate the water, and if you’re looking for a cheap option, then a sponge filter is your best bet. You can usually get one with an air pump for 10-20 bucks.
When it comes to diet, most crayfish are pretty similar and you can feed them pretty much anything mentioned in the article. Let me know if you have any more questions.
Jocelynn Cruz says
Around the south of Texas, and it’s fone if you don’t know this, but if I put it in clean water (no mud) it won’t hurt it, right?
Jocelynn Cruz says
Fine**
Robert Brand says
It will be fine putting it in clean water as long as there is no chlorine in it. What kind of water are you going to use?
Robert says
Hey Robert, is aquarium salt ok to use in my red claws tank?
Robert Brand says
Sorry, but just to clarify, do you mean Australian red claw crayfish?
Robert says
Yes
Jade says
Hi ?I recently bought 2 white ghost lobsters (I think that what they are called) . They are in a +/- 10g/30 litre tank. They seem happy. The pet store said my large one is a male and 2 smaller ones are females. The large one is about 3 inches and the 2 small ladies just over 1.5 inches. Is their any way to tell their age by these sizes?
The male has been hiding in his cave most of the time but comes out for food while the female are very active. I can’t seem to find much info on these guys so just wordering if I can find out their approximate age? And if that large male could mate with the small females ? Or must they be similar in size?
Robert Brand says
Crayfish reach maturity very quickly, so for that size they have to be relatively young. The only way to accurately determine a crayfish’s age is by reading the growth marks on it’s stomach – not something you can normally do while they’re still alive.
The size difference won’t mean much when it comes to mating at they’re normally sexually mature after a few months. What you do need to be concerned about is that they’ll try to eat each other during molting. So make sure there are many, many hiding places for them.
Jade says
thank you that is very helpful!
this morning i woke up to 1 of my smaller females melting. she’s still in progress here. there are many hiding places. do i put food in for the others that aren’t melting while she is? or should i wait for her to be finished> the big guy and other lady are chilling in hiding spots at the moment.
Robert Brand says
You should definitely put in food, as a well fed crayfish is less likely to go hunting. So keep feeding them normally until the crayfish is done molting.
Emme Rogers says
Is there a difference between a baby lobster and a crayfish? If so then how do you tell the difference? Cause I just got one today that it really small (probably around 1 centimeter) and has a bluish silver color from what I can tell. Also can you feed them the shrimp pellets or just the cabbage?
Robert Brand says
Normally, when you purchase a baby lobster, it’s a just colourful name for crayfish (unless you’re in a very specialized store, buying a saltwater lobster). And it’s best to feed it a varied diet. A good base for the diet is shrimp pellets, with lightly blanched vegetables offered every few days. Also, make sure to remove any uneaten vegetables after 24 hours or it will start to break down. And when it comes to vegetables, they prefer romaine lettuce, zucchini, cucumbers, and broccoli. I don’t know anyone who feeds cabbage, though I’m not sure if there is a reason for that, or just the bad smell when you lightly boil it. lol
Ryan says
I’ve read different things on what size tank is optimal for keeping a crayfish. If you have a ten gallon tank, would you do weekly ten percent water changes?
Thanks in advance.
Dana says
We’ve had a blue crayfish in our tank for about 5 months now, and have just noticed she is carrying eggs. Other fish are in the tank but no other crayfish. What are the chances the eggs are fertilized? Will it be a danger for our other fish if the eggs hatched within our 55 gal tank? We definitely didn’t plan to breed crayfish and want the best for the other fish ultimately.
Robert Brand says
Some crayfish can store sperm, but my understanding is that blue crayfish cannot. It’s likely the eggs will be consumed or abandoned soon in the tank. But even if the eggs were to somehow hatch, they wouldn’t be a danger to the fish until they reach maturity. The biggest danger is to each other since crayfish hatchlings are cannibals and will rapidly eat each other as they grow in a fish tank.
Jozie says
My crayfish I have her on her own. Why is she dropping some of her eggs? Also does black eggs mean they are new eggs?
Robert Brand says
It could be that the eggs aren’t fertilized. There are some crayfish that can store sperm and at least one species that doesn’t require a male to breed, but mostly likely, if the eggs are dropping they’re not viable. And new eggs are a kind of blackish-blue. They turn brown when they’re going bad.