Fish That Eat Algae

“Algivore” is a common term for algae-eating fish.

Table of Contents

Contrary to popular belief, there are many types of algae-eating fish in the world. From benthic fish like plecos to free swimming fish like guppies, there are many fish that feed on algae . These fish are a popular choice for aquarium enthusiasts, as they use these fish as an effective means to reduce the amount of clean-up in their tanks. Let’s explore the many different types of algae-eaters in the world and discover how they can be the perfect addition to your aquarium

Common Plecos

The common pleco is one of the most efficient algae eaters in the world. They are renowned for their ability to help keep algae populations in check. Not only that, but they’re especially helpful when it comes to string algae, which can be really tricky to get rid of. Having too much string algae in any water body can cause oxygen levels to drop. A healthy amount of common plecos in any pond or tank can prevent string algae from taking over the habitat.

Common plecos are super effective at removing algal build up from all types of tanks. Credit: Anthony Corda/Wikimedia Commons

Koi Fish

With their bright colors, koi are probably the most recognizable fish in the world—but they’re often mistaken for adult goldfish. Koi may nibble on some algae, but they don’t have the same passion for it as common plecos do.

Koi FIsh
Koi fish can grow incredibly huge and should be housed in small ponds. Credit: Neutrality/Wikimedia Commons

Instead, these beauties much prefer insects or fish food! These fish are often housed in conjunction with smaller algivores like common plecos, mollies, or guppies.


Goldfish are the most beloved fish in the world, and, for many of us, the first fish we ever learn about. Similar to koi, goldfish are more of algae-snackers than algae-eaters, as they prefer to eat algae occasionally rather than rely on it as their primary source of nourishment.

Goldfish are one of the most popular fish in the world. Credit: Wikibluff

Common Mollies

Also known as “algae suckers,” common mollies tend to suck all the algae off surfaces like rocks or pebbles in tanks or ponds. Mollies are very small fish; they’re only 3 to 6 inches in length. So, if you’re looking to keep your tank or pond algae-free, you’ll need quite a lot of them, or you’ll need to house common mollies in conjunction with other fishes like common plecos.

Common mollies are also known as “algae suckers.” Credit: Hugo Torres/Wikimedia Commons

Common mollies have a remarkable rate of reproduction, which means that their population size will grow quickly. As their population grows, so will their effectiveness as tank-cleaners!


Guppies are one of the most-loved aquarium fish in the world. Not only are they beloved, but they are also incredibly helpful. They are similar to common plecos and common mollies in that they can help clean an impressive amount of algae from your tank. Guppies are incredibly efficient as algae control, and can even be used in larger ponds.

Guppies are small and colorful fish that make good additions to any aquarium.Credit: Marrabbio2/WIkimedia Commons


Carps are one of the best measures to use against algae in your tank or water body. Many different types of carps, like the common grass carp or the triploid grass carp, can all be employed at the same time in your tank as algae eaters. Their massive appetites help them demolish entire populations of aquatic plants.

Grass Carps snack on populations of musk grass. Credit: Wikimedia Commons

Before buying yourself a carp for algae control, it is important to correctly identify the type of algae you have growing in your tank or pond, as grass carp do not feed on the more common types of algae like string algae. Rather, they prefer musk grass, a type of green algae. Similarly, even triploid grass carp will not touch string algae and show a demonstrated preference for musk grass.


Catfishes are another excellent choice of fish to house in your tanks. From twig catfish to loaches, these fish are easy to care for and make for good algae control elements. Otocinclus catfish are a particularly good choice for tanks that have a problem with brown algae.


Loaches are super effective algae-eaters. Similar to carps, there’s a wide variety of loaches to choose from for your pond.


Pond loaches are mildly effective algivores. They do not grow to a large size, so you will require a large number of these fish in your pond. Pond loaches are used in combination with other algivores, like catfishes or carps.

Pond loaches are mild algivores. Credit: Wikimedia Commons

Weather Loaches

Weather loaches are absolute units. They’re as powerful as vacuum cleaners when it comes to algae control. They will eat anything that touches the bottom of your pond. However, before you place a bulk order for weather loaches, bear in mind that these fish love eating fish eggs and will have a negative effect on the overall population in your tank.


Weather loaches can grow to be about 20 inches long. Credit: George Chernilevsky/Wikimedia Commons

Algae Eaters

Algae eaters do exactly what they’re named for – they eat algae. The Siamese algae eater might be the best algae control fish on this list. They don’t have a preference for a particular type of algae and will feed on any algae that grows in their habitat. They even finish off types of algae that other algae eaters shy away from. For example, many algivores can not stomach black beard algae. They’re docile species and do not get territorial when other fish are introduced in their tank. Their easy-to-care-for temperament makes them the perfect fish for beginner hobbyists.

Algae Eaters
Chinese algae eaters are aggressive and must be housed with semi-docile or docile species. Credit: Garthhh/Wikimedia Commons

Alternatively, you can also use Chinese algae eaters. These fish are easy to care for and do well in tanks and ponds alike. They’re aggressive algae eaters who supplement their herbivore diet with multiple different types of algae.


Benthic: Refers to the lowermost ecological region of a water body.


Algae: A group of simple plants that do not flower and lack normal plant parts like stems, roots, or leaves. These plants generally grow in or around water.


Docile: Refers to an easygoing or submissive nature.


Territorial: A term used to refer to a type of behavior displayed when defending territory.

Readability: 62


Flesch Kincaid Grade Level: 8

Adams, Cristopher. 18 Best Algae Eaters For Your Freshwater Aquarium (Fish, Shrimp & Snails). October 13, 2021.


Aquarium Co-op. 10 Best Algae Eaters For Freshwater Aquariums.

Aquarium Co-op. How To Fight 6 Types Of Algae In Your Fish Tank.,an%20aquarium%20seem%20more%20natural.99


Sanders, Jessie. The Truth About Fish Eating Algae. October 4, 2022.


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