Do Fish Eat Algae & Which Types Eat Algae?

Do Fish Eat Algae Which types eat algae

There are a surprising number of fish that eat algae, which can help a lot with keeping the tank clean. 

If you want to set up the best possible aquarium, it’s important that you explore your fish options. Algae can build up very quickly, but the right fish can save you a lot of time and effort.

Types of Algae

First we will take a look at some of the different types of algae that can form in your aquarium.

1. Gold Slime

This type of algae looks like green specks on the glass of the tank, but it can quickly take over if it’s not kept in check. It is especially common with aquariums that don’t have much light.

2. Green Water

Green water algae are not very common at all, but it can be extremely harmful to your fish. You won’t be able to find any fish that will eat these algae. If you have this kind of algae in your tank, you’ll have to change the water immediately.

3. Thread Algae

When you see green strands that almost look like hair floating in your aquarium, it is probably thread algae. One of the things that make this type of algae so dangerous is that it grows very fast.

4. Green Slime

This is a very common type of algae, but it quickly gets eaten up by fish. This makes it relatively harmless, but you don’t want to let it get out of control.

5. Brush Algae

Brush algae get its name from its dense, clumpy appearance. It sticks to pretty much any vegetation it can find in an aquarium. The good news is that there are plenty of aquatic pets that will gladly devour it.

fishes in aquarium

Do Fish Eat Algae?

Not all fish eat algae, but there are many kinds that do. Algae don’t offer fish a whole lot of nutritional value, which is why they have to eat tons of it. There are quite a few fish that will spend a vast majority of their waking time gobbling up all the algae they can find.

The fact is that some fish eat more algae than others. There are also fish that don’t eat algae at all. Having an algae eater in your tank can help you keep it clean without having to do a lot of unnecessary work. 

Best Fish that Eat Algae

If you are looking for the very best algae eaters to fill your tank with, you’ll definitely want to take a look at this list.

1. Orocinclus Catfish

The type of catfish is known for eating massive amounts of algae on a daily basis. While these fish are only about two inches long as adults, they can consume impressive quantities of algae. This is one of the best fish you can put in your tank for this purpose.

2. Pond Loach

The Pond Loach is an incredibly adaptable fish that can easily survive in a variety of water conditions. It can get very big though, so you’ll need a very large aquarium. While these fish don’t eat quite as much algae as some others, they are very beautiful. You can keep the water in the tank quite cool or warm. One of the reasons that people love these fish so much is because they are so low maintenance.

3. Siamese Algae Eater

There is no question that the Siamese Algae Eater makes for a great addition to just about any tank. It can eat a large number of algae on a daily basis, keeping your aquarium nice and clean. These fish eat almost any type of algae with only one or two exceptions. They can get pretty big—up to six inches. It’s not recommended that you keep them with timid fish that are easily bullied.


4. Common Plecos

You’ll find that common plecos can be great for consuming algae as well. They will devour any algae that might grow on the plants in your tank. They do require a lot of space due to their size; you’ll need a minimum 300 liter tank. You also won’t be able to keep them with smaller fish, as they will most likely eat them. This is definitely not an ideal choice for inexperienced fish keepers.

5. Twig Catfish

The twig catfish used to be pretty rare, but it’s now a little easier to find. These fish will eat a lot of different kinds of foods, including algae. You will have to devote a lot of time to keeping them healthy though. This includes carefully monitoring and adjusting the pH level of the water. It’s also important that these fish are kept in a high-oxygen environment. You’ll also need to invest in a high-quality filter that is fairly powerful.

6. Chinese Algae Eater

The Chinese algae eater isn’t the very best choice when it comes to keeping your tank clean, but it does eat a good amount of algae on a daily basis. Keep in mind that these fish are pretty aggressive as adults, so you cannot keep them with any small or timid fish. They need to be kept with their own kind, as they will likely attack other types of fish.


  • There are several different types of algae, some of which grow faster than others.
  • Green slime algae are by far the most common in aquariums.
  • The Orocinclus Catfish is one of the best choices for keeping your tank clean, as it eats tons of algae each day.
  • The Pond Loach is another good choice, though it does require a very large tank to truly thrive.
  • The Siamese algae eater is a large fish that shouldn’t be kept with smaller ones that are easily bullied.
  • Common plecos are also great for keeping algae to a minimum, but they require a huge tank as well.
  • Twig catfish are fairly popular nowadays, but they can be very challenging to care for.
  • The Chinese algae eater is pretty aggressive as an adult, but it does eat a fair amount of algae.
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