The Best Algae Eaters for Aquariums

If Benjamin Franklin were alive today and a fish-keeper, he would probably amend his famous statement to state, ‘In this world nothing can be said to be certain, except death, taxes, and algae.’ And it wouldn’t be far from the truth, since virtually everyone who owns an aquarium – from the novice, to the experienced aquarist – struggles with algae at some point.

But thankfully, the task of vigorously scraping and cleaning algae doesn’t have to fall completely to you, and there are numerous fish and invertebrates who can help you clean algae in an aquarium. But these algae eaters should never be purchased just to eat algae – they need to be provided with the right tankmates and proper conditions for them to thrive.

So, before you purchase any algae eaters, make sure to research them in depth: Learn what type of food they need, whether they are compatible with other fish, and most importantly, whether their fish tank is large enough for them.

Bristlenose Pleco – These fish are generally considered to be the best all-around algae eaters. Not only do they do well in most community fish tanks, but they can also adapt to a wide variety of water types. When you combine that with a suckermouth designed specifically to graze on algae, you have the perfect algae eater for most aquariums.

But just because these fish eat algae, doesn’t mean their diet doesn’t need to be supplemented. They should always be provided with a high-quality sinking pellet designed specifically for herbivore fish, and provided with a varied selection of lightly blanched vegetables. When choosing a sinking pellet, one of the best choices is Hikari Tropical Algae Wafers. I’ve used this food with great success for many years, and algae eaters love them.

Also, to keep these fish healthy, you absolutely must provide them with driftwood to rasp on in their aquarium. Driftwood provides much needed fiber in their diet, and they can sicken and even die if there isn’t any driftwood available.

But if you provide these few simple things to keep your bristlenose pleco healthy and happy, you’ll be amazed at the amount of algae they can clean from aquarium surfaces.

If you want to learn more about these fish, you can read the Bristlenose Pleco Guide here.

Siamese Algae Eater – Often mistaken for the Chinese Algae eater (which is a terrible algae eater), or the false Siamese Algae Eater (another poor algae eater), these fish are among the best algae eaters for an aquarium – assuming you can find one of them to purchase. They tend to be rare in pet stores, and usually require a trip to a specialty fish store to find.

But if you can find them, there are few fishes that can compete with their voracious appetite for algae. And they are one of the only fish available in the hobby that feast on red algae. They will also eat brush algae – another algae few algae eaters will consume.

These fish should be kept in schools, and prefer densely planted aquariums, as the juveniles prefer to rest on broad leafed plants. An aquarium containing these fish should have neutral or slightly acidic water, though they can adapt to a high pH.

If you can find these fish, and have the room for a school of them in your aquarium, they’re an excellent addition to help in the battle against algae.

Twig Catfish – These suckermouth catfish are an excellent algae eater, but their docile and sometimes skittish nature makes them unsuitable for most aquariums; Which is a shame, since they constantly browse on algae, and if they were more suitable for community tanks, they would be among the best algae eaters available.

Like bristlenose plecos, they can’t survive on algae alone and their diet should be supplemented with sinking algae pellets (like this one, Hikari Tropical Algae Wafers), or other herbivore food. Also, to help these fish feel at ease, their tank should contain driftwood, and should be densely planted.

Several of these fish can easily be kept in an aquarium, though large fish such as cichlids, or even large tetras should be avoided. It can’t be stressed enough that these fish can easily be killed or injured by aggressive fish.

Ameca Splenden – Probably one of the most underrated fish in the hobby, Ameca Splendens are an amazing fish in their own right. But they also make an excellent algae eater – assuming you can find any fish to keep them with. Theses fish can be very aggressive, especially the males and few similarly sized fish can compete with them at feeding time.

But if you keep these fish, they can help with the algae cleaning, and you will regularly spot them browsing on the algae in an aquarium. They will also eat hair algae, something few other algae eaters will touch. While they don’t have a specialized mouth for eating algae like many of the catfish on this list, they can still make a big difference in a fish tank – albeit only one small mouthful at a time.

If you want to learn more about these fish, you can read the Ameca Splenden Care Guide here.

American Flagfish – The perfect fish for any patriotic American – or just anyone who wants to try and keep a killifish – these fish are highly sought after for their impressive coloring and their algae management ability.

Along with Ameca Splendens on this list, they are one of the few fish that happily consume hair algae – one of the more difficult algaes to get rid of. Unfortunately, a taste of algae isn’t the only thing they share with Ameca Splendens and they also have an aggressive nature. They are notorious fin nippers – so add these fish to an aquarium with caution.

But they happily consume algae, so it’s often worth adding these fish to a semi-aggressive tank. And while you may never get the same level of cleanliness as you would with a suckermouth catfish, they are still very dedicated to their job, and will help to keep an aquarium clear of algae.

If you want to learn more about these fish, you can read the American Flagfish Care Guide Here.

Otocinclus Catfish – Perhaps one of the most dedicated algae eaters on this list, the Otocinclus Catfish, or oto cat, is a fragile and relatively difficult fish to keep. They will only thrive in larger aquariums (29 gallons and up) and need to be kept in schools of at least six.

But if you have a mature, well-maintained aquarium, and can find some healthy otocinclus catfish, then these little fish can punch well above their weight in algae consumption. They can consume staggering amounts of algae, and constantly browse on algae in a tank.

Even though they do well on a diet mostly comprised of algae, they should still regularly be offered herbivore food, or lightly blanched vegetables.

Ramshorn Snail – While these snails are an excellent algae eater, they can also be a danger to many aquatic plants. If there isn’t sufficient food in an aquarium, then they may begin to consume fine leafed plants – something no fish-keeper wants.

But as long as there is sufficient food and algae, these snails make an excellent addition to most aquariums – assuming of course, you don’t mind having a fast reproducing snail in your fish tank.

Ramshorn snails do an excellent job cleaning algae off ornaments, aquarium glass, and even the substrate. Some of the larger species can work wonders on algae infested aquariums.

They do, however, require slightly alkaline, moderately hard water to maintain their shells. Beyond that, they have virtually no care requirements, and will thrive in most aquarium. A word of warning though: keep them away from snail eating fish like most loaches, puffers, and larger cichlids.

If you want to learn more about these snails, you can read the Ramshorn Snail Care Guide here.

Malaysian Trumpet Snail – These little snails are an amazing algae eater and I personally keep them in all my tanks. Unlike most other snails which can be unsightly, they hide in the substrate during the day and usually only emerge at night. Though they may start to pile up on the substrate if there is a population explosion (usually from overfeeding).

These snails have few requirements to keep them healthy, and only need slightly alkaline, moderately hard water to keep their shells in good shape.

But if you keep them healthy, you’ll find them quickly multiplying, and eating copious amounts of algae from virtually every surface in the aquarium. They are especially helpful in eating algae off the aquarium glass, and if there is a significant coating of algae, you’ll often see long lines of clean glass where they’ve gone over the algae like a lawnmower.

If you want to learn more about these snails, you can read the Malaysian Trumpet Snail Care Guide here.

Nerite Snail – If you like snails, but don’t want to risk them spreading through your aquarium like a Biblical plague, then nerites are probably the best choice for you. Long considered a staple of a well-rounded aquarium cleanup crew (they’re often paired with Amano shrimp), these snails are colorful, and best of all, can’t reproduce in freshwater.

Nerite snails can consume prodigious amounts of algae, and a handful of nerite snails can keep most aquarium surfaces completely clean. The only downside is they may plaster eggs across the aquarium, so you may trade scraping algae, with scraping snail eggs.

Amano Shrimp – These shrimp are probably the most popular algae eating invertebrate – and for good reason – they can consume a staggering amount of algae. They do well in both small and large tanks, although greater numbers of shrimp may be required to keep larger tanks clean.

It’s important to keep them with docile, smaller fish, as larger fish may attempt to prey on them. It’s also important to provide them with a sinking food when kept with fish, as they need food to supplement their algae diet.

But there are few algae eaters better suited for planted tanks, and they come with the added benefit of being safe around nearly all aquatic plants. These shrimp are a must have for an aquarium cleaning crew.

If you want to learn more about these snails, you can read the Amano Shrimp Care Guide here.