The gender of the Swordtail Fish could be easily differentiated because the males have a signature long anal fin that females do not have in common. Besides that, the males are also easily being identified by their signature 'sword' tail that are much longer than the females' tails.

The Swordtail Fish often give birth to many fry but a big portion often being eaten up. The males would then have mock fights with the females and hence develop territories. The male will splay their fins, wriggle furiously and strut around the female. The female usually swims away while the male is persistent, slipping in and fertilizing the female at the right time. She will thereafter give birth to the young ranging from twenty to several hundreds and then turn around and eat them, hence many green plants should be provided for the young to hide in.

The Swordtail Fish can be kept in a community tank with other fishes like mollies, platys and tetras etc.