Breeding the threadfin rainbowfish
Lays a few eggs each day over several days on fine-leaved plants, aquatic moss or nylon mops.
Step by step
Group of 8+.
A planted tank with fine mops.
Frequent feeding, good conditions.
A small number of eggs each day for several days; eggs hatch in 7-10 days depending on temperature.
Fine infusoria, microworms.
- Tank too turbulent
- Large tank mates
- Poor food
Male or female
Mature males have a fan-shaped first dorsal fin and very long thread-like filaments on the second dorsal, anal and pelvic fins, and are larger and more colourful; females are plain with short fins.
Can I breed it in my tank?
- Use a separate small tank with a sponge filter and spawning mops, so the eggs aren't eaten.
- Good for a first breeding project.
Day-by-day plan
Typical for egg scatterers
- 14 days beforeCondition the parents
Feed live or frozen food twice a day. Keep males and females apart if you can.
- Day 0Spawning
Eggs are scattered over mops or fine plants, often at first light. Remove the parents straight after.
- Day 1Eggs hatch
Most eggs hatch in 1–2 days. Keep the tank dim and remove white (fungused) eggs.
- Day 4Free swimming, first food
Fry use up the yolk and start swimming. Feed infusoria or liquid fry food several times a day.
- Day 8Baby brine shrimp
Switch to newly hatched brine shrimp or microworms. Start small, daily water changes.
- Day 21Crushed flake
Add finely crushed flake. Sort fry by size so the big ones don't eat the small ones.
- Day 60Ready to move
Most small fish reach about 2 cm in 2–3 months and can join the main tank.
A general guide for this breeding type. Days change with temperature and species.
Simulator: guided
Feed live or frozen food twice a day. Keep males and females apart if you can.
Simulator: try it yourself
Set up a virtual breeding tank and see what would likely happen.
- Without live or frozen food the parents aren't in breeding condition.
An educational estimate from the breeding rules, not a promise.