Guppy

Looks how to spot one

Small scaled livebearing fish; males with enlarged, colourful tail and dorsal fins

A slim little fish with a clear difference between the sexes. Males are smaller and carry bright patches, spots or stripes plus showy tail and dorsal fins, while females are larger, rounder and mostly silvery grey. Breeders have created many fin shapes, including veil, triangle, fan, flag, lyre, spade, round, pin and single or double sword tails.21

Personality what they are like

Calm and non-aggressive towards tankmates. Males spend much of the day displaying and following females, so the group dynamic is lively. They are best kept away from fish that nip fins.32

Daily activity how busy a day looks

An active mid-water and surface swimmer that appreciates open swimming space alongside planted areas and floating plants to explore.3

Grooming and care the hands-on bits

Suggested aquarium from about 41 litres with a footprint of roughly 45 x 30 cm, well planted and with floating vegetation. Water around 17 to 28 C (about 23 to 24 C is ideal), pH 7.0 to 8.5 and moderately hard to hard water (roughly 8 to 30 dGH). Tolerates slightly brackish water.31

Home where they are happiest

In the wild it lives in warm springs, streams, ditches and canals, doing best where there is plenty of algae, edge vegetation and aquatic plants. At home a planted tank with dense cover gives both adults and fry places to rest and hide.13

Food basics what goes in the bowl

Omnivore. Wild guppies eat zooplankton, small insects and their larvae, algae, diatoms and detritus. Aquarium-bred fish readily take most foods, so a mix of quality flake or granules with small live or frozen foods works well.123

Company who they like around

Best kept in a group with several females for each male, which spreads out the males' attention. Gets along with other livebearers, rasboras, corydoras and tetras.3

The story where it all began

The species was first scientifically described by Wilhelm Peters in 1859 from fish collected in Venezuela. A few years later Robert John Lechmere Guppy, a naturalist in Trinidad, sent specimens of the local 'millions' fish to Albert Gunther at the British Museum, who named them Girardinus guppii in his honour. That name was later folded into Poecilia reticulata, but the common name 'guppy' stuck. Because guppies eat mosquito larvae, they were released into waterways around the world for mosquito control, and they now live on every continent except Antarctica. Guppies also became one of the most studied fish in biology, used as a model for research on evolution, ecology and behaviour, while hobbyists developed countless fancy strains through selective breeding and organised show standards through groups such as the IFGA, founded in 1965.2534

Recognised by the official bits

IUCN Red List

Assessed as Least Concern (2020)1

International Fancy Guppy Association (IFGA)

Hobby association founded in 1965 that runs judged fancy guppy shows in the USA to its own show standards, with more than 70 colour classes4