Otocinclus

The otocinclus is a tiny freshwater armored catfish (family Loricariidae) native to South America. It has a slender, mottled brown-and-cream body with a dark lateral stripe and a sucker mouth used to graze algae from surfaces. Several similar species are traded collectively under the name oto. It is exceptionally peaceful and highly social, and must be kept in groups of at least six to thrive. Otos are prized as gentle, effective algae eaters that pose no threat to plants or other fish. They require a mature, stable aquarium with soft green algae growth, as they can starve in a spotless new tank. A largely herbivorous grazer, the oto should have its diet supplemented with algae wafers and blanched vegetables when natural algae runs short. Sensitive to poor water quality and acclimation stress, it does best in well-established planted community tanks.