All fish / Loricariidae

Otocinclus

Otocinclus vittatus

Also known as oto, otto, oto cat, dwarf sucker, dwarf suckermouth catfish, otocinclus catfish, striped otocinclus, otocinclus vittatus, ปลาแคระดูดกระจก, ปลาออตโต้, ikan oto, オトシンクルス

A small, slim armoured catfish with a sucker mouth, sandy to olive body and a dark stripe running from the snout to the tail base. Fish keepers buy it mainly to graze soft algae and biofilm off glass, leaves and wood in planted tanks, and it is gentle enough for nano communities.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

4 cm

Temperature

22 to 28 °C

pH

6 to 7.5

Smallest tank

60 litres

Keep as

Group of 6 or more

Diet

Herbivore: biofilm and soft algae, plus algae wafers, blanched courgette, cucumber and spinach

Swims

Bottom of the tank

Lifespan

3 to 5 years

Water

Freshwater

Wild range

South America: Amazon, Orinoco and Paraguay river basins (Brazil, Bolivia, Paraguay, Venezuela, Colombia, Peru)

Breeding

It lays sticky eggs on glass or plant leaves after chasing behaviour, often triggered by cool water changes, and the parents give no care. Spawning occasionally happens in well kept planted tanks, but raising the tiny fry on biofilm and fine foods is tricky.

Good to know

Most stock is wild caught and many starve soon after import, so choose plump, active fish and add them to mature tanks with plenty of algae. Several similar species, such as O. affinis and O. macrospilus, are sold under the same name.