Guppy

Guppy is a small tropical fish. It rivals the goldfish as the world's most popular aquarium pet. Guppies have beautiful, featherlike tails and fins. Many male guppies have several bright colors in a pattern on their body, and they often look like small jewels. Adult males are about 1 inch (2.5 centimeters) long. Female guppies grow about twice as long and are mostly gray. More »