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.

Guppy Fish

One of the most popular freshwater aquarium fish is the P. reticulata species, or commonly known as the Guppy. The Guppy in this picture taken by judhi, does a nice job of posing for the camera.


Also known as the millionfish or fancy Guppy, these fish are an excellent addition to the non-aggressive community fish tank. Special breeding programs have produced unique color strains in the species. Native to Trinidad, and regions of South America, the fish was discovered in Trinidad in 1866 by Robert John Lechmere Guppy. Although he wasn't the first to write about this species, the name "Guppy" stuck. Here's a few characteristics and items to think about when purchasing Guppies:

  • Minimum tank size 20 gallons.
  • Easy to care for.
  • Grows to 2 - 2.5 inches.
  • 65-81 degrees F, ph 5.5-8.0, KH 10-30
  • Come in many beautiful colors.
  • Guppies are live-bearers.

Usually you can distinguish the difference between Guppy males and females by coloration, and fin formation. Generally, the males are smaller, yet have brighter colors than the females. Also, female guppies have a rounded anal fin, and a pregnancy patch located near the bottom portion of their body.

Because these fish are live-bearers, you can have fun breeding them in your aquarium. Be warned though, if you try Guppy breeding, adults will eat the fry if they're left alone. You'll want to set your fish tank up specifically for breeding, if you're going to attempt raising them. This requires an environment with floating ferns and a breeding box which will protect the fry.

I have never tried Guppy breeding, but have friends that have raised fry. If you decide to try it, get ready to have a large amount of guppies to take care of. You'll want to make sure you have prepared a home for them. A pregnant Guppy can drop as many as 200 fry.