Dwarf Top Minnow (Heterandria formosa)

Family: Poeciliidae

Dwarf Top Minnow — a Poeciliidae from 中北美洲, easy-going community fish with lively breeding. Reaches 2.7–4 cm; loose colonies; heavy planting shelters the fry. 20–26 °C.

Care parameters

Water temperature
20–26 °C
pH
7–8
GH hardness
9–19 dGH
Adult length
2.7–4 cm
Minimum tank
25 L
Water layer
Middle of the water column
Difficulty
Moderate
Temperament
Easy-going community fish with lively breeding
Origin
中北美洲

Species overview

Heterandria formosa, a member of the family Poeciliidae, is native to 中北美洲. An unkillable beginner classic that nonetheless shows its best in hard, alkaline, well-planted water. It swims in mid-water. Adults reach 2.7–4 cm. Loose colonies; heavy planting shelters the fry. Keep water hard and alkaline, plant densely, and expect fry — forever. Maintain 20–26 °C at pH 7–8. A solid choice for a well-planned community tank.

Native biotope

Habitat
Warm freshwater streams and lakes
Flow
Still to gentle current
Dissolved O₂
Moderate oxygen levels

Aquascape & hardware

Substrate
Fine sand and gravel
Hardscape
Driftwood and smooth stones
Plants
Hardy common aquarium plants

Temperament, diet & tankmates

Schooling
Loose colonies; heavy planting shelters the fry
Diet
Unfussy — quality flakes, some greens, occasional treats
Recommended tankmates
  • Corydoras catfish — Share the bottom peacefully
Avoid keeping with
  • Large predators — The fry buffet ends everything

Breeding & notes

Sexual dimorphism
Subtle external differences
Breeding method
Livebearer — females deliver 20–100 fry every few weeks