All fish / Lebiasinidae

Least Pencilfish

Nannostomus minimus

Also known as least pencilfish, minimus pencilfish, dwarf pencilfish, small pencilfish, nannostomus minimum, ナノストムス・ミニムス, 小铅笔鱼

A tiny, slim pencilfish with a dark lateral stripe running from snout to tail, a golden band above it and red patches in the fins of males. It is kept for its delicate colours and calm nature in planted soft water tanks with other very small fish.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

2.5 cm

Temperature

24 to 28 °C

pH

5 to 7

Smallest tank

40 litres

Keep as

Group of 8 or more

Diet

Omnivore: small live and frozen foods such as daphnia, cyclops and baby brine shrimp, plus fine flake

Swims

Middle of the tank

Lifespan

3 to 5 years

Water

Freshwater

Wild range

Guyana, Suriname, French Guiana and the lower Amazon and Rio Negro basins, Brazil

Breeding

It scatters eggs among fine plants and gives no parental care, so the adults will eat the eggs if left together. Spawning is possible in soft, acidic water with dense plants or a mesh, but the tiny fry need infusoria at first.

Good to know

Its very small mouth and timid nature mean it struggles to compete with lively fish, so keep it with tiny peaceful tankmates. It is often confused with Nannostomus marginatus and other striped pencilfish.