10 Small Algae Eaters for Freshwater Aquariums

Posted by on 08/16/2023

If your freshwater aquarium has been taken over by algae, you can enlist the help of other aquatic life forms to assist in algae removal. However, not all hobbyists have a large enough tank to introduce new species on a whim. 

In this post, we'll recommend 10 of the smallest algae eaters that you can introduce into your nano aquarium.

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Our Top 10 Smallest Algae Eaters

When selecting a small-sized algae eater, you'll want to make sure it doesn't grow to an unanticipated size. Luckily, these 10 options will stay small, so that you can focus on other areas of your tank.

Amano Shrimp

Arguably the best algae eater in the hobby, this shrimp will only grow to be about an inch in length.

Named after famous aquarist Takashi Amano , these shrimp will consume every type of algae in your tank, including the infamous black beard algae.

Image of an Amano Shrimp
Joan Carles Juarez/Shutterstock.com
An Amano Shrimp

Blue Dream Shrimp

While any color morph of Neocaridina Davidi will consume certain types of algae, our favorite are the blue dreams. These shrimp sport a dark-blue coloration, making them easy to spot in a crowded aquarium.

Hobbyists should have no problem spotting these shrimp munching on available algae in their tanks.

Image of a Blue Dream Shrimp
Serhii Shcherbyna/Shutterstock.com
A Blue Dream Shrimp perched on an aquatic plant

Assassin Snails

Assassin snails are technically carnivores, frequently cruising around the tank to feed on pest snails. 

However, once these mollusks have run out of meaty options, they'll turn to diatoms and other algae films present in your tank.

Image of an Assassin Snail
A top down view of an Assassin Snail

Mystery Snails

Also known as the Spike-topped Apple Snail, Mystery Snails grow to about 2 inches in length, and will feed on algae, leftover fish food, and dead plants. They've even been known to eat duckweed but, fortunately for hobbyists, will ignore other types of aquatic plants.

Image of a Mystery Snail
Chapulines/Wikimedia Commons
A Yellow Mystery Snail

Pygmy Cory

While these fish require protein-rich fish food, their diets can also be supplemented with algae. Hobbyists that have diatoms or green dust algae growing along the substrate will benefit from the addition of a few pygmy corydoras.

Image of a Pygmy Cory
AquaTuer/Wikimedia Commons
A Pygmy Corydoras

Siamese Algae Eater (requires 20-gallon tank)

The largest algae eater on our list is the Siamese Algae Eater, and hobbyists looking to acquire this species will need at least a 20-gallon aquarium.

Similar to dwarf corys, these fish prefer to lounge along the substrate, where they'll pick at algae wafers, leftover fish food, and naturally occurring algae, such as diatoms.

Image of a Siamese Algae Eater
aleander2137/Wikimedia Commons
A Siamese Algae Eater

Otocinclus vestitus

Hobbyists that are fending off dust algae growing along their aquarium glass should strongly consider adding a few Otocinclus fish. These fish, often abbreviated as "Otos", love to munch on any dust-like algae that are available.

If enough dust algae is present, you can easily see the result of their algae-eating abilities. 

Image of an Otocinclus Vestitus
Fremen/Wikimedia Commons
An Otocinclus vestitus fish

Nerite Snails

Next on our list is the Nerite snail, and while the species may be best known for the intricate design patterns on their shells, these mollusks will also consume algae as part of their diet. While these snails may not be as fast at eating algae as shrimp and fish, what they lack in speed they make up for with their unique appearance.

A Nerite Snail
TheJammingYam/Wikimedia Commons
A Nerite Snail

Ramshorn Snail

If you've ever seen a bright red or deep blue aquatic snail, you've likely seen a ramshorn. These snails feed primarily off of green and brown algae growing along the substrate, and will also clean off driftwood and aquatic stones, such as seiryu stones

Some hobbyists may consider Ramshorns to be pest snails, as the species is hermaphroditic, meaning two organisms of any sex are capable of producing offspring.

A Red Ramshorn Snail
A Red Ramshorn Snail

Malaysian Trumpet Snail

While Nerites and Ramshorns are probably the fastest algae-eating snails on our list, one cannot discount the Malaysian Trumpet.

Growing to be about an inch, these snails are slow movers, but will occasionally munch on algae growing along the aquarium glass.

Malasyian Trumpet Snail
A Malaysian Trumpet Snail


That wraps up our list of 10 small algae eaters for freshwater aquariums. Now that we've provided you with a few options, which small algae eater do you think you'll choose? Let us know in the comments, and be sure to visit our inverts category, where you can find many of the species we've mentioned for sale by other hobbyists.

Image of Miles Harrison

Miles Harrison

With over a decade of aquarium experience, Miles can be found writing about saltwater and freshwater aquariums. When he’s not writing about fish, you can find him going for a run or building websites, such as this one!