Algae eater

Algae eater is a common name for many bottom-dwelling fish that feed on algae. Algae eaters are important for the fishkeeping hobby and many are commonly kept by hobbyists. Some of the common and most popular freshwater algae eaters in aquariums include:

Some of the common and most popular saltwater aquarium algae eaters include:

Several of the well known algae eaters in wild nature in salty water include:

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Wikipedia