Puberty the sword reaches to 6-8 months. If you bought a fry, be sure to ask the seller how many months the fry, and from the age of their puberty, keep a "diary of observations", in order to isolate the female from the tank in case, if you want to breed fish. But even if you made fish not to divorce, the female is still worth it to transplant before birth, as soon as she is too weak, and her and the fry can eat the other inhabitants of the aquarium.
Fertilization occurs inside the female and takes about 2 days, and the remaining sperm is stored in her body until, until you Mature new eggs. Pregnancy occurs within 4-6 weeks. Its duration is very much affected by water temperature (should be not below 20-25°C), photoperiod and feeding regime.
To determine whether pregnant female sword. it is possible to appear at her anal fin dark spot. During this period, her abdomen inflates and remains the same regardless of that she is hungry or full. Just before birth the female begins to look for secluded places in the aquarium or, on the contrary, rises to the surface. The abdomen is almost square.
If you notice that the fish is pregnant, immediately put it in a prepared aquarium, in which you must place as much vegetation as weakened immediately after birth the female will not mind "snack" their kids, and bushes will help them to avoid this.
Usually birth in females of the swordtail happen in the morning. In the litter up to 200 fry (the ratio of females and males is 3:1). After birth the female it is best to transplant. You should feed the fry as often as possible, including a diet high in protein.