Swordtails are livebearers, which means that the female gives birth to live young rather than laying eggs. The gestation period for swordtails is typically around 28 days, and the female will usually give birth to the fry in the early morning hours. The fry are born fully formed and are able to swim and feed on their own immediately.
Swordtail fry are very small and delicate, and they require a lot of care in order to survive. The fry should be kept in a separate tank from the adults, and the water should be kept clean and at a temperature of around 78 degrees Fahrenheit. The fry should also be fed a diet of small, live foods, such as brine shrimp or daphnia.
With proper care, swordtail fry will grow quickly and will eventually reach sexual maturity. Swordtails are typically sexually mature at around 6 months of age.