What to do with the female after she gave birth?
When you are sure that the female guppy has finished giving birth, remove her from the breeding tank and put her together with the male that you intend to mate her or continue to mate her with.
It is shown that female guppy is highly receptive (attractive) to males shortly after birth. The male guppies will constantly monitor the cloacal region of the female guppy for signs of receptivity. The receptivity of the female is short, about 12 to 48 hours after birth.
It is likely that the female signals her receptivity chemically. The male becomes hyperactive when exposed to a substance released by the female which has been identified as an estrogen. Some breeders believed that if the male successfully impregnant the female within 48 hours after she gave birth, there will be higher chance that the next birth will be from this male sperm. The earlier he impregnant her, the higher will be the chance.