Xiphophorus hellerii

Alternative names

 * Swordtail, ,

Sexing

 * Males have a long "sword" on their tails. Females have a fan shaped anal fin and males have a stick shaped anal fin (gonopodium). Males are larger in length than females, up to 7" if you include the sword.

Breeding

 * As livebearers, they breed readily in the tank environment without much encouragement and produce up to 200 fry every 4-8 weeks. Adults will eat young fry, so dense planting such as Java Moss or placing new fry into a breeding trap should ensure fry survival. Never put a pregnant female into a breeding trap as this will cause undue stress and possibly cause her to abort the fry. Swordtails can hybridise with Platys.

Tank compatibility

 * Mid-swimming fish that are generally peaceful, but males can become aggressive with each other. Keep at least two females per male to keep the males from fighting. It is possible to keep an all male tank but you should have at least 4-5 and expect to have to watch for "bully" fish. Swordtails can hybridise with Platys, and if they are kept in a mixed tank male Swordtails will pursue female Platys and visa versa.

Diet

 * A variety of foods accepted including pellets, flake, daphnia, frozen tubifex worms and brine shrimp.They also like to eat some blanched vegetables like courgette, cucumber or lettuce

Feeding regime

 * Feed once or twice a day. Will allow hand feeding.

Environment Specifics

 * Well planted with open swimming spaces. Multiple hiding places are essential.

Behaviour

 * Generally not a shoaling fish but do prefer to be in groups, males may chase each other.

Identification

 * Males have a long "sword" on the tail. These fish come in a variety of colours with many different fin styles. Some forms have been selectively bred to even have the sword extension not only on the bottom of the fin but the top also. Female Swordtails can be mistaken for Platys or even Mollys depending on colour.