Least killifish
Heterandria formosa
FishFreshwater
- Care level
- Easy
- Temperament
- Peaceful
- Recommended tank
- 20 L
- Maximum size
- 3.5 cm
- Temperature
- 18–26 °C
- pH
- 6.5–8
- Group size
- ≥ 6
- Diet
- Omnivore
Care at a glance
The least killifish from the south-eastern United States is one of the smallest fish in the world: females stay barely two centimetres and males smaller still. Despite the name it is not a killifish but a relative of the guppy and platy.
Its breeding is unusual: instead of one batch, the female releases a few young at a time over a period of weeks. It copes fine with cool water, is peaceful and likes to stay among fine planting; larger fish will simply eat it.
Related species
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