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What Fish Will Eat the Poop in Your Aquarium? 9 Waste-Eaters

What Fish Will Eat the Poop in Your Aquarium? 9 Waste-Eaters

Dealing with fish waste is such a bother! Luckily, if you know what fish will eat the poop in your aquarium, you’re already one huge step ahead!

You might be surprised to find out many waste-eating fish exist. And no, we’re not talking about corydoras only! Many common aquarium fish species will love to eat waste and keep your tank clean. 

While many novice aquarists are disgusted at the thought of their lovely colorful fish eating poop, this is just a part of nature. 

In fact, you should be glad that poop-eating fish are so common. They help you clean your tank!

If you want to know what fish will eat the fish poop in your aquarium, you’re in the right spot. I’ll give you a list of 9 waste-eating fish and explain why the truth might not be as straightforward as you might think.

Do Fish Eat Poop?

Okay, I’ll admit it – I might have misled you a bit. No fish will intentionally eat fish poop. This is just a misconception that seems to be as old as the hobby itself. 

No fish species can survive eating poop alone. Poop is a waste – inedible matter that animals have excreted as it has no nutritional value (it can make a decent plant fertilizer, though!).

However, some fish are more likely than others to eat the poop by accident. They mistake it for food pellets and swallow it, making aquarists believe they have willingly eaten it. 

There is no harm when fish eat poop. Still, some novices believe that, because their fish ate waste, it doesn’t need any additional food. This is wrong. Even the so-called waste-eating fish will still need regular food. 

In fact, most of the time you’ll notice your fish spitting out poop after they’ve swallowed it! This should be the first indication that they don’t consider waste a tasty meal.

Also, just because you have poop-eating fish doesn’t mean you don’t need to clean your tank

No amount of fish or other animals that eat waste can replace manual cleaning and good filtration systems. 

What Fish Will Eat the Poop in Your Aquarium?

Now that we have the waste-eating fish dilemma out of the way, it’s time to answer the main question – what fish will eat the poop in your aquarium?

As mentioned before, all fish species might eat a small amount of poop by accident. They mistake it for tasty food pellets or smaller animals as it floats in the water and eat it. 

However, some fish are more likely than others to eat and swallow it

Below are 9 fish species that are more likely than others to keep your aquarium poop-free:

Corydoras Catfish

corydoras catfish poop eater

We cannot talk about poop-eating fish without starting with corydoras! These fish are often called cleaners due to their habit of eating anything that reaches the tank floor.

In fact, many experts consider getting a cleaning crew consisting of corydoras, plecos, snails, and shrimp a mandatory part of keeping a tank!

Fortunately, corydoras are peaceful fish that thrive in groups. You can easily add them to almost any tank, as long as you are certain the other fish won’t eat them.

Corydoras are among the best tank cleaners you can get. They will clean up after other fish rather efficiently by eating anything remotely edible. This is the main reason why they are so widespread in the fish keeping community.


sailfin molly poop eater

Mollies are a popular freshwater fish species that originate from southern US states and Central America. They live in rivers, streams, lakes, ponds, and any other freshwater habitats. 

However, it isn’t uncommon to find them in brackish waters, as well – although, despite the rumors, they don’t need salty water to survive and breed.

This is an omnivorous fish that feeds on many things, including algae, worms, insects, plants and plant material, even small crustaceans! Do not keep mollies with your blue velvet shrimp unless you want your shrimp to be fish food!

As mollies aren’t picky eaters, they might swallow food from time to time. Most of the time, though, they’ll spit it out. 

If you have a molly that is constantly eating fish poop, this is usually a sign that something’s wrong. Your molly might be really hungry, or suffering from some health condition. 



Parrotfish isn’t a single fish species. In fact, there are dozens of tank fish that belong to the parrotfish family!

This tropical saltwater fish lives in rocky coasts, seagrass beds, and coral reefs. They are mostly herbivores, but plants aren’t providing them with enough nutrients. As such, they have found a way to complete their diets. You’ve guessed it – they eat fish poop.

In fact, a research conducted by the University of Texas at Austin’s Marine Science Institute has found out that other coral reef fish eat about 85% of feces produced by fish that eat plankton. Out of that, about 90% of the waste was consumed by surgeonfish and parrotfish alone!

Many smaller parrotfish species are commonly found in saltwater tanks, and they are sure to provide you a helping hand with cleaning!

Common Plecos

pleco catfish in aquarium

The common pleco is one of the best-known fish in the fish-keeper community. Its natural habitat is the rivers of South America, but now you can find it in various parts of the world.

Plecos are freshwater bottom dwellers that eat food leftovers that have sunk to the substrate. Also, they mostly eat algae, so they’ll help keep your tank clean. 

Next to that, plecos might accidentally consume fish poop that has fallen to the bottom of the tank

Still, fish poop shouldn’t be its main food source. Plecos need a healthy, balanced diet, so make sure to add some fish pellets that will sink before other fish can eat it.


goldfish in freshwater aquarium

All aquarists know about goldfish! This is probably the most popular fish species world-wide, and it’s easy to see why. They are easy to care for, rather healthy, and simply gorgeous!

At the same time, they are known for eating anything they can fit in their mouth! This includes fish poop.

Goldfish are scavengers. Even so, most goldfish will spit out fish poop the moment they swallow it. However, a goldfish that is hungry won’t mind eating poop

Overtime, this can be a huge problem. If a goldfish eats too much poop it can become sick or even die. 

As such, even if you feed your goldfish regularly, make sure you clean poop using other methods, as well. 


spotted scat fish in aquarium

Also known as a tiger scat, spotted butterfish, or a spotted scat, scat is a fish native to the Indo-Pacific region. This freshwater fish is commonly kept in tanks while small, as adults can reach the length of up to a foot!

Their name comes from a Greek word skat, which means ‘dung’ or ‘feces’. Similarly, their latin name, scatophagus, comes from the words scat and phagus (which means ‘to consume’). The literal translation of its name would be fish poop eater!

This alone tells you enough about scat’s eating habits. In nature, they are scavengers that eat worms, insects, small crustaceans, and plant nature. However, they have been seen eating feces from time to time.

Scats are a common addition to freshwater tanks due to their colorful appearance and hardy nature. 


beautiful surgeonfish

I’ve already mentioned surgeonfish while talking about parrotfish, so by now you already know that this is yet another coral reef fish that eats feces. 

This is a peaceful fish that is often kept in tanks with other saltwater species. They are among fish commonly found to eat feces in their natural habitat. 

It’s important to note that, just like parrotfish, surgeonfish isn’t a single species, but rather a fish family consisting of more than 80 marine fish species. 


platy in aquarium

Platy is yet another fish species that isn’t a picky eater. Quite the opposite – this fish will eat anything tiny enough to be considered food

This freshwater fish is rather hardy, which makes it an excellent beginner fish. It comes in a variety of colors, although you’ll usually find it in red or golden, with a black tail. 

In nature, platies will eat algae, insects, plants, and even small crustaceans. However, they’ll try to munch on everything and anything. If they are hungry, they will eat fish poop.

However, just like with goldfish and most other fish species, you shouldn’t allow your platy to eat too much feces. Otherwise, its health might be compromised – but knowing how to make aquarium salt might help treat various conditions to an extent. 


Tilapia is a freshwater fish native to Africa and the Middle East. However, due to its ability to adapt to various conditions, it is now found worldwide. 

Colorful tilapias have been kept in tanks not just for their good looks but for belief they eat poop – and this rumor isn’t entirely wrong.

In nature, tilapias feed on algae. In fish farms, their diet consists mostly of corn and soybean meal. However, when they don’t have enough food, tilapias will survive on eating poop for a while. In fact, they are so hardy some farmers feed them food leftovers!

Keep in mind that most widespread tilapia species are kept in tanks in farms and not as a part of someone’s house collection. However, a few colorful varieties, such as the red tilapia, can be found in local pet stores.

Do Snails Eat Fish Poop?

Snails eat many impurities that can be found on the bottom of the tank or on various objects and decorations. This is why many tank keepers believe that snails also eat fish poop. 

Despite this, snails do not eat fish poop. Although they might attempt to munch on it from time to time, mostly they’ll just avoid it. 

However, snails will eat most of the biowaste they can find. As such, they are considered rather effective cleaners

Just don’t expect them to do all the job for you! Even if you keep snails, you’ll still have to do all you can to make sure your tank is crystal clear. Don’t worry – you don’t have to remove the fish or snails to do this!

Do Shrimp Eat Fish Poop?

Shrimp are another animal many people consider poop-eaters. However, this, too, is a myth.

While shrimp will eat biofilm and many other impurities, the only time when they eat fish poop is when they’ve mistaken it for some other tasty food.

However, they’ll eat most other leftovers, such as dead fish, plants, and algae. They’ll do an amazing job of keeping your tank clean, and many aquarists have reported they don’t have to clean the tank as often when they have shrimps and snails in it. 

While some shrimp might eat a bit of feces from time to time, this alone isn’t enough to notice a huge difference.

The Bottom Line

So, what fish will eat the poop in your aquarium? The answer is many, and none. 

Many fish species will munch on anything they can find, including fish poop. Some might even add it to their diet from time to time. 

However, no fish species can truly eat poop or survive by eating nothing but feces. Fish poop isn’t nutritious and it can only cause harm to most aquatic animals. 

While these 9 fish species can help you out, you’ll still need to remove most of the fish poop on your own. 

I hope this article helped you understand better why fish poop isn’t a proper food source, but also what fish might give you a helping hand in keeping everything as clean as possible.

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