Breeding the least killifish
Very easy and breeds readily with both sexes present. Females use superfetation (several broods developing at once, nourished through a placenta-like link), so fry are born a few at a time rather than in one brood. Adults usually leave the fry alone.
Step by step
Keep a group of 6 or more; they pair themselves.
Densely planted 20 L tank with floating plants, java moss and gentle filtration.
Stable temperature and plenty of tiny live food.
A few fry every day or two (up to about 40 over a 10-14 day period); gestation about 4 weeks. Fry take powdered food and Artemia nauplii at once.
Fry take baby brine shrimp or powdered flake right away and need cover.
- Large tankmates eating the fry
- Strong filter currents
- Keeping alone
Male or female
Males are much smaller (about 2 cm) with a very large gonopodium; females reach about 3 cm.
Can I breed it in my tank?
- Good for a first breeding project.
Day-by-day plan
Typical for livebearers
- 28 days beforePregnancy
A dark 'gravid spot' grows behind the belly. Gestation is usually about 4 weeks.
- Day 0Birth
Fry are born ready to swim. Thick plants or a breeding box keep them safe from adults.
- Day 0First food
Feed crushed flake, baby brine shrimp or microworms 3–5 times a day.
- Day 28Sexing starts
Males start to show color and a pointed anal fin. Separate them if you want to control lines.
- Day 90Adults
Most livebearers are grown and can breed at about 3 months.
A general guide for this breeding type. Days change with temperature and species.
Simulator: guided
A dark 'gravid spot' grows behind the belly. Gestation is usually about 4 weeks.
Simulator: try it yourself
Set up a virtual breeding tank and see what would likely happen.
- The female gave birth.
- With no plants or breeding box, the adults ate most of the fry.
An educational estimate from the breeding rules, not a promise.