Well,
As a matter of fact, Sword Tales dont lay eggs (roe), they give birth to live young, which end up being around 2-6mm at birth, then grow within a couple of weeks to become adults (around 2-3cm).
It depends on how craw the fish is
When fish eggs hatch the little fish can swim immediately.
Generally, cichlid eggs such as those laid by convicts hatch in three to five days. Convicts are relatively easy fish to breed.
Hatch time for fish eggs is completely dependant on the species of fish. Some fish take only a few days, where others can take over a month. by : Jan kosiek
It takes about 2 to 3 months for salmon eggs to hatch. Use the link below to get more information on the life cycle of this amazing fish.
The time it takes for fish eggs to hatch varies greatly depending on the fish species. It can range from as little as a few days to several weeks. Water temperature and other environmental factors also play a role in the incubation period.
Arowanas are mouth breeders, that is, the male will carry the fertilized eggs in his mouth and protect the young once they hatch. See the link below for a good overview of this fish's reproductive habits.
Different fish species need different temperatures and each have different hatching/development time.
It takes 2 to 3 days for the eggs to hatch.
2 to 5 days usally but only having two percent chance to live they will be white if dead.
They do not gestate so there is no 'gestation period' Japanese fighting fish (Betta splendens) are bubble nest builders and lay eggs which are tended by the male in the nest until they (hatch).
Clownfish hatch into larvae that are swept away from the nest as soon as they hatch; so clownfish stay with the parents as eggs for 10-14 days.