The Black Molly is an interesting fish and makes a great addition to any community aquarium. It is one of the most popular fresh water fish around. Its beautiful appearance, friendly temperament and hardiness make this fish a great selection for beginners especially.

The Black Molly is one of the gentlest fish available for freshwater tanks. They fit well into any community aquarium and will not bother any other fish. However, they are not extremely active fish and should not be kept with aggressive fish, such as Barbs. They enjoy a tank with lots of space and a moderate amount of rocks and plants. They will not bother live plants.

The gentleness of the Black Molly makes it an attractive fish. However, the Black Molly's appearance is also an extremely attractive feature. They have a completely jet black body, with large streaming dorsal fins. There have been some slightly colored variations produced by man, which are also very beautiful. Their fins resemble those of Beta Fish. Males and females are easy to distinguish visually. The male Black Molly has a larger, pointed dorsal fin. The dorsal fin on female Black Mollys is smaller and more rounded. In addition, like other livebearers the male has a sex organ called a gonopodium, which acts as a sperm-delivering device (similar to a penis in mammals). The female does not have a gonopodium she has a vent. Their short life span is the only connotative feature of the Black Molly. They will only live to be three years of age in an aquarium.

The Black Molly, or Poecilia sphenops, is originally from Columbia and Mexico.

Black Mollys are easy to care for. They need warm water temperatures, from 79 to 86 degrees. Black Mollys need a pH of 7.5 to 8.2 and like a small amount of salt in their water. They will eat all of the usually fish foods, flakes, blood worms, glass worms, brine shrimp, plankton and tubifex worms, as well as fresh vegetables. They will also eat algae that grow in the tank.

If breeding is desired, there should be two females for every one male. Black Mollys are livebearers. Once born, the fry will become food for the parents, so they should be separated.