Colorful, energetic, and famously easy to breed, the Guppy (Poecilia reticulata) is one of the most popular freshwater aquarium fish in the world. Selective breeding has transformed this naturally small livebearer into an astonishing collection of aquarium varieties. Guppies can display enormous fan-shaped tails, intricate mosaics, metallic blues, fiery reds, yellows, greens, blacks, and almost …
