10 Best Algae Eaters for Freshwater Aquariums

You need help to control algae growth in your aquarium. In this top 10 list of amazing algae eaters, we’ve gathered animals that are not only safe for aquatic plants but can often work together for increased effectiveness.

Aquarium Co-Op is a wholesaler of thousands of live plants. We are committed to keeping them as healthy as possible. That’s why we utilize the most effective algae eaters in the aquarium hobby for our holding tanks. One of the most important lessons we have learned is that each algae eater has its own mouth and body that is best for eating certain types of algae. We mix different types of algae eaters into our aquariums to eat the various kinds of algae. 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. This list has more information about how to get additional help.

1. Reticulated Hillstream Loach

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. Using their strong gripping abilities, they can easily clean large, flat surfaces like vertical aquarium walls, rocks, and broad plant leaves. Think of them like your personal window washers for diatoms and other flat kinds of algae.

Sometimes they can be territorial towards their own species, so you should only get one or three loaches per group. If you can keep them in water coolers with a stable pH and feed them high quality sinking food like Repashy gel foods, you might see some baby loaches appear in your aquarium.

There are many species for hillstream and brook loaches like Sewellia lineolata and Beaufortia kweichowensis.

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. Meet Caridina multidentata, a clear-brown dwarf shrimp that can reach 2 inches (5 cm) in length. These rare creatures will eat hair and black beard algae. 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 can be easily bred in an aquarium. However, you won’t get any baby shrimp until they are raised in saltwater.

3. Nerite Snails

Coming from the Neritidae family, we have a very diverse group of small, ornamental snails that are adept at both scavenging and eating 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 gorgeous varieties, such as red racer, zebra and horned. But we like olive nerite snails. They seem to be the hardest. 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

One cherry shrimp, or Neocaridina darvidi, isn’t as effective at algae eating than 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. Read more about them in our cherry shrimp article.

An army of bright red cherry shrimp exploring a lush forest of green aquarium plants is a delightful sight to behold.

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. They are similar to the hillstream locach and can be found hanging out on the aquarium glass, or even the leaves. Otos are prone to being underfed, so make sure you give them plenty of Repashy Soilent Green and vegetables like canned green beans and blanched zucchini slices. 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 Eater

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. In order to encourage older SAEs to eat more algae, you might have to reduce their food portions. As with hillstream loaches, SAEs can be a little territorial with their own or similar-looking species, so choose to either get one individual or at least three in a group for more algae-eating power.

Siamese Algae Eaters are not as aggressive as Chinese, and can grow twice as large.

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, 2.5-inch (6 cm), algae eater is a great choice for cutting out hair algae, black beard algae, and other fuzzy types. However, it can also damage delicate plants 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 can be used to eat algae and vacuum up food crumbs. 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 are well-known for their bristles on the snout. Females, however, have a clean-shaven appearance.

9. Molly Fish

Mollies, a Poecilia genus livebearer, are a popular species that can live in both fully fresh and fully saltwater waters 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. They can be bred into many different colors, patterns, fin types and body shapes by the aquarium hobby. If they are given enough food and hiding places, they will reproduce easily. 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

Certain barbs like the rosy bar (Pethiaconchonius) are fond of fuzzy algae such as hair, staghorn and thread algae. This peaceful species can grow to three inches (7.6cm) in length and is available in neon, normal and long-finned versions. 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.