10 Best Algae Eaters for Freshwater Aquariums

To get rid of unsightly algae from your aquarium, you will need to have some help. We’ve compiled a top 10 list with amazing algae eaters. These animals are safe for aquatic plants and can often be used together for greater effectiveness.

At Aquarium Co-Op, we’ve sold thousands of live plants, and one of our main concerns is keeping the plants as free of algae as possible. For our holding tanks, we use the most efficient algae eaters from the aquarium hobby. We have learned that every algae eater is unique and has the right mouth and body shapes to eat specific types of algae. Therefore, we mix different species of algae eaters in our aquariums to consume the different kinds of algae that may appear. If your tank is large, you can start by using a small number of algae eaters. Once you adjust the lighting and nutrients in your tank, wait one month to see how they affect the algae. If you need additional help, consider getting more clean-up critters from this list.

1. Loach in Reticulated Hillstream

This oddball fish is one of the coolest-looking algae eaters you will ever see. The fish can grow to 3 inches (7.6cm), and it looks almost like a miniature stingray. It is covered in intricate black stripes and golden brown dots. They can clean flat surfaces such as rocks and vertical aquarium walls. They can be thought of as your personal window washers for algae and diatoms.

Sometimes they can be territorial towards their own species, so you should only get one or three loaches per group. Keep them in cooler waters with a stable pH, feed them high-quality sinking foods like Repashy gel food, and you may be lucky enough to see some baby loaches pop up in your aquarium.

There are many species that live in hillstreams and brooks, including Beaufortia kweichowensis and Sewellia ligneolata.

2. Amano Shrimp

While hillstream loaches are great at consuming flat types of algae, you may also need a more nimble-fingered algae eater that can reach into narrow gaps or tear off chunks of fuzzy algae. Caridina multidentata is a clear-brown dwarf shrimp, which can grow to 2 inches (5 cm). They are one of the rare animals that will eat black beard algae and hair algae, but only if you don’t feed them too much. Because of their small size, you will need at least four (or more) of them to make a difference in the growth of algae. For more details on their care requirements, read the full species profile here.

Amano shrimp are easy to breed in your aquarium. But, you won’t get any baby shrimp unless you raise them in saltwater.

3. Nerite Snails

The Neritidae family includes a variety of ornamental snails. These snails are skilled at both eating and scavenging algae. They are particularly adept at removing the toughest green spot algae, as well other algae that can be found on plants, driftwood and decorations. They are white and resemble a sesame seed-like egg, which means that they won’t hatch in freshwater unlike most aquarium snails. This will ensure that you don’t get an out-of control population. There are many varieties of snails to choose from, including red racer, zebra, horned and tiger. However, we prefer olive nerite because they are the most durable. To ensure healthy shell development, make sure to add calcium to the water with Wonder Shell or crushed coral.

Green spots algae can be very hard to get off rocks and plants. But nerite slugs are one of few animals that can do it.

4. Cherry Shrimp

If you did a direct, head-to-head comparison, a single cherry shrimp (or Neocaridina davidi) isn’t as efficient at algae eating as an amano shrimp. However, these brightly colored dwarf shrimp breed easily in home aquariums, and with a decent-sized colony, they provide excellent preventative maintenance against the buildup of excess food and algae. Their tiny limbs are perfect for picking through the substrate, plant roots, and other tiny crevices, and they’re happy to consume anything that’s digestible. At 1.5 inches (4 cm) long, cherry shrimp come in almost every color of the rainbow and can be easily sold for profit to your local fish store or other hobbyists. You can read more about them in the cherry shrimp article.

A delightful sight to see is an army of brightly colored cherry shrimp in a lush forest filled with green aquarium plants.

5. Otocinclus Catfish

The catfish of the Otocinclus genus are commonly known as otos or dwarf suckermouths because they typically stay around 2 inches (5 cm) in length. Their smaller, slender bodies allow them to fit into tighter spaces than other algae-eating fish. Like the hillstream loach, their mouths are ideal for eating diatom algae from flat surfaces, and you can find them usually hanging out on the aquarium glass or plant leaves. Otos are susceptible to becoming starved so be sure to give them lots of Repashy Soilent Green, as well as plenty of vegetables such as canned green beans and blanched zucchini pieces. For more information on how to care for these adorable catfish, read our full article here.

Otocinclus catfish are a schooling fish, so try to get at least three to six of the same species to help these shy creatures feel safe and comfortable.

6. Siamese Algae Eating

Crossocheilus oblongus (also known as SAE for short) is a 6-inch (15 cm) cleaner fish that is commonly used in larger aquariums. Their downturned mouths are well-suited for eating hair algae, black beard algae, and leftover scraps in the fish tank. Because SAEs have the ability to consume more algae than juveniles, it is not surprising that they eat more of the fish. Therefore, you may need to reduce food portion sizes in order to get older SAEs interested in eating algae again. SAEs are territorial and may be territorial with other species. If you want to increase your algae-eating power, get at least three of them together.

Siamese algae eaters are not the same as Chinese algae eaters, which are much more aggressive and can get twice as big.

7. Florida Flagfish

Jordanella floridae is also known as the American flagfish because of the male’s beautiful red stripes and rectangular shoulder patch that resembles the flag of the United States. This voracious algae eater, measuring 2.5 inches (6 cm), has the right mouth to eat hair algae, black beard algae, and other fuzzy alga types. It can however sometimes cause damage to delicate plant leaves. If you have an unheated tank with other fast-swimming tank mates, this killifish may be the right algae eater for you.

As a native of North America, flagfish can thrive in cooler water environments without any aquarium heaters.

8. Bristlenose Plecostomus

Plecostomus are one of the most well-known algae eaters, but they often get very large as adults and aren’t suitable for the average home aquarium. Thankfully, bristlenose plecos from the Ancistrus genus are peaceful catfish that stay between 4 to 5 inches (less than 13 cm), making them perfect for a 25-gallon tank or larger. Their suckermouths are designed to consume algae, clean up food crumbs and keep driftwood clean. However, remember to feed them a well-rounded diet of sinking wafers, frozen bloodworms, and Repashy gel food to make sure they get all the necessary nutrients.

Males have bristles around their noses. While females are more clean-shaven, Males are also known for having a cleaner face.

9. Molly Fish

Mollies, which are popular livebearers of the Poecilia genera, live in full freshwater to fully saltwater in the Americas. Their flat grasping jaws, flat stomachs, and ability to pick at any type of algae, regardless of its surface or hardscape, make them a popular livebearer. Their variety of fin shapes, colors, fin types, and patterns have been carefully selected by aquarium hobbyists. They are easy to reproduce when there is plenty of food and hiding places for their fry. As a heads up, fancy mollies are often raised in brackish water fish farms, so if you sense health problems with your new fish, consider adding aquarium salt and extra minerals to help them thrive.

10. Rosy Barb

Some barbs, such as the Rosy Barb (Pethia Conchonius), have a preference for fuzzy algae like hair and staghorn. This tranquil species can grow up to 3 inches (7.6cm), and it comes in three different varieties: neon, long-finned, and normal. Similar to the flagfish, rosy barbs can be kept in unheated aquariums with other speedy tank mates. To lessen any aggression, make sure to keep them in groups of at least 6 to 10 (ideally with more females than males) in a 29-gallon tank or larger.

Unlike most barbs, Pethia conchonius are relatively peaceful and won’t bother your other fish as long as you get a decent-sized school to keep them entertained.

Want more information on how to get algae under control? Read our complete article on the most common types of algae found in freshwater aquariums and how to get rid of them.