All fish / Loricariidae

Otocinclus

Otocinclus macrospilus

Also known as oto, otto, dwarf sucker, oto cat, otocinclus catfish, large-spot otocinclus, macrospilus oto, dwarf otocinclus, ปลาซัคเกอร์แคระ, ออตโต้, オトシンクルス, オトシンクルス・マクロスピルス

A small, slim suckermouth catfish with a dark stripe along each side and a large rounded spot at the base of the tail. It is popular in planted aquariums because it spends all day grazing soft algae and biofilm off leaves and glass without bothering other fish.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

3.5 cm

Temperature

21 to 27 °C

pH

6 to 7.5

Smallest tank

54 litres

Keep as

Group of 6 or more

Diet

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

Swims

Bottom of the tank

Lifespan

3 to 5 years

Water

Freshwater

Wild range

Upper Amazon basin in Peru, Ecuador and Colombia

Breeding

It lays sticky eggs on leaves and glass after the males chase the females, much as Corydoras do, and the fry need a steady supply of very fine algae and biofilm. Spawning sometimes happens by chance in mature planted tanks, but rearing the young takes effort, and most fish sold are caught in the wild.

Good to know

Wild-caught fish are often starving when they arrive, so add them only to a mature tank with plenty of algae and feed them extra vegetables. They are often sold mixed up with O. vittatus and O. vestitus, which look very similar, and with the Chinese algae eater, which gets much larger and aggressive.