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.
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.
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.
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.