Algae eater is a common hello name for many bottom-dwelling fishes that feed on algae. Algae eaters are important for the fishkeeping hobby and many are commonly stocked by the trade.

• The true algae eaters are cypriniform fishes of the genus Gyrinocheilus, family Gyrinocheilidae. There are three species in this genus with the Chinese algae eater, Gyrinocheilus aymonieri, the most common. Small specimens make good community fish but may become territorial when elder.
• The Siamese algae eater, Crossocheilus siamensis, is a more gregarious and tolerant cyprinid that ranges up to 15 cm. It is the only fish that will graze on "black brush algae" (freshwater Rhodophyta, or Red algae), but even so will eat anything else in preference.
• American-flag fish, Jordanella floridae, are also dependable algae eating fish.
• Many loricariid catfish of South America such as Otocinclus and Plecostomus species constantly graze algae and biofilm, although `Plecos` eat much less frequently as they near adulthood.
• Bristlenose catfish, is another group of popular and efficient algae eaters.
• Some freshwater shrimp are also excellent algae eaters. One shrimp well known for its ability to clean an aquarium is the Amano Shrimp.