Fancy Guppy

Poecilia reticulata

The fancy guppy (Poecilia reticulata) is the domesticated aquarium form of a small livebearing fish native to tropical streams and pools in northern South America and the Caribbean region. Generations of selective breeding have produced wide variation in tail shape, body color, pattern, and fin size, from delta and veil tails to mosaic, snakeskin, tuxedo, and solid color strains. Males are usually smaller and brighter than females, while females carry developing fry internally and give birth to free-swimming young.

Guppies are common beginner fish, but good results still depend on warm stable water, mature filtration, gentle current, and enough cover for fry. They breed readily, so keepers plan sex ratios, nursery space, and culling or placement before buying pairs. Fancy long-finned lines may be less hardy than plain wild-type stock and can suffer with fin-nipping tankmates. Breeders track strain, color, tail form, and outcrosses closely because attractive adults do not always produce uniform offspring.