Swordtail care sheet

Swordtails Xiphophorus helleri

Live bearing Tooth Carp Family or Poeciliidae. 

Natural Range:

Swordtails are native to Mexico to Guatemala 

Maximum Size and Longevity:

Swordtails can grow up to 13cm. 

Water Quality:

Livebearers generally require harder water with pH over neutral:  Temperature: 22oC — 27oC  pH: 7.0 — 7. 8  General Hardness:200 — 300 ppm 


Swordtails are omnivorous surface feeders with a large appetite. They will eat most aquarium fish foods and also graze on any algae growing within the aquarium. We suggest feeding a mix of flakes or pellets with ingredients like spirulina to help provide the necessary nutrients to aid in optimum growth and health. The addition of live foods like brine shrimp and daphnia, when available will also benefit X. helleri. The fry are easy to raise due to their larger size when compared to egg laying species, approximately 7 to 10mm in length when born. They will feed on finely ground dry foods. 


Swordtails are generally suitable for keeping in community tanks with other medium sized fish. It should be noted that when they are fully grown they can be very active and may out-compete some smaller or less active species for food. Some adult Swordtails can be aggressive and develop the habit of fin nipping. 

Colour and Varieties:

Wild Swordtails are generally a dull green colour with a small extension to the tail fin. Selective breeding has produced a vast array of colour variations such as red, tuxedo, albino, green, red and white and numerous other colourations. The ‘sword’ extension of the tail of male fish has also been greatly enhanced in selectively bred fish, and more recently more elaborate fins has been developed such as Hi- Fin and Lyretails. 


Mature male swordtails are easily identified by the long sword -like extension to their tail. The females also have a dark spot near the anus called the gravid spot – this is the area in which the fry develop before being born. Livebearers have the common trait that they give birth to free swimming young (ovoviparious), instead of egg laying like most other fishes. To achieve this, male livebearers have a modified anal fin called a gonopodium that is used to facilitate internal fertilization of the female. Once fertilised, the eggs mature inside the oviduct of the mother. The eggs then hatch internally and give ‘birth’ to the resultant offspring soon after. Swordtails are prolific breeders and successful breeding in a community tank will generally occur in one that is well planted as the plants provide hiding places for the fry to escape from being eaten by other fish. A note about breeding is that they are capable of hybridising with the closely related Platy (X. maculates) and produce fertile offspring (hybrid offspring are generally infertile). This has been an important factor in developing the large colour variations seen in both species.