Swordtail Fish

Full of eggs, and relaxing in her plastic breeder box, Statico's female swordtail (below) will soon be giving birth to young fry. Adding these live-bearing fish to your peaceful, community aquarium, make a welcome addition.


Many popular Swordtails (Xiphophorus helleri) found in pet stores are hybrids, and come in assorted colors. Marigold, Black Nubian, Pineapple, Neon , Red Wag, and Red Velvet Swortails, are just a few commonly found varieties of this species. You might think the name comes from the sword shaped caudal fin protruding off the lower end of the male. Actually, the swordtail name is derived from the male's anal fin. You can determine the sex of the fish though, by the "sword" shaped fin. Male swordtails have one. Females don't. Notice the lack of this on the female swordtail in the picture. If you're interested in stocking the swordtail in your communty fish tank, keep the following in mind:

  • Minimum tank size is 20 gallons.
  • Tank Parameters: 65-82 degrees F; pH 7.0-8.2; KH 12-28.
  • Swordtails are Omnivores.
  • Peaceful fish perfect for community tanks.
  • Grow to 4" in length.
  • Easy to care for.

As live-bearing fish, the aquarium hobbyist can try their hand at raising fry. You can learn more about swordtail breeding here. These fish are able to reproduce in high numbers. Unfortunately, in the wild, they have become a nuisance in some countries where they were introduced to an area not indigineous to the species.

I've had the swordtail fish in my own aquariums. They are very pleasant, and swim quietly around. You could easily keep them with the Guppy, Dwarf Gourami, and I have even stocked them with Tiger Barbs.