Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Poecilia reticulata


Guppy, Poecilia reticulataGuppy, Poecilia reticulata
Photos by Andy Rapson


General Notes:

The ever popular guppy is one of the all time favourite fish with in the hobby. Colourful, outgoing, peaceful and hardy, the perfect beginners fish. Or at least that is how it used to be. Sadly todays guppies are showing the effects of poor breeding and inbreeding. They aren't as hardy or long lived as they used to be but their popularity is as great as ever despite this. The guppy that we see in our tanks is quite unlike guppies found in the wild. Tank bred guppies which have been bred for the aquarium trade are larger, more colourful and with longer flowing fins. It is because of their long flowing fins that their tank mates must be carefully chosen, obviously any fish which has a tendency to nip fins should be avoided.


Guppies will accept all suitably sized food. Good quality flake as a staple diet with treats of live or frozen food. They will also eat algae and detritus.


Male guppies are much smaller and much more colourful than female guppies. They are one of the easiest of all fish to sex. Like all other livebearers the males have a modified anal fin to facilitate internal fertilisation.


Guppies are extremely prolific, they give birth to live young after a one month pregnancy. The fry are independent from the moment they are born and are larger at birth than the fry most similarly sized egg laying species. It is advisable to keep more females than males, this is to prevent the males guppies from pestering the same female all the time. With good care guppy fry should reach adult size at around twelve weeks old or sooner. Once mated a female guppy is able to store the sperm and produce several broods of fry from a single mating. Guppies will prey on their own fry if given a chance so it is better to use a separate aquarium which is densely planted for a breeding tank and then to remove the female after she has given birth. The use of breeding traps and nets is out dated and rarely produce good results. If a female guppy is fed on lots of live food prior to giving birth she will be less likely to prey on her own fry.

Wild status

Guppies wild status is unknown due to insufficient data. But the species has been widely introduced well beyond its natural range.

Information at a glance

pH: 7 - 8
dGH: 5 - 15
Temperature: 18 - 28°C (64 - 82°F)
Diet: Omnivore
Size: 3.5cm 1.5in)
Min tank size: 60 litres
Difficulty level: Easy
Aquarium type: Community
Swimming level: All levels

Distribution and habitat

distribution map for Guppy, Poecilia reticulata

Origin: South America: Venezuela, Barbados, Trinidad, northern Brazil and the Guyanas. But they have been introduced in many other places and have become a pest species due to their prolific nature.

Habitat: Found in weedy ditches and canals and in various other habitats, ranging from highly turbid water in ponds, canals and ditches at low elevations to pristine mountain streams at high elevations. Occurs in wide variety of habitats with low predation pressure, usually in very small streams and densely vegetated lakes and springs.


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Poeciliidae
Genus: Poecilia
Species: P. reticulata, Peters, 1859

Common name:

Synonyms: Acanthophacelus guppii, Acanthophacelus reticulatus, Girardinus guppii, Girardinus reticulatus, Lebistes poecilioides, Lebistes reticulatus, Poecilioides reticulatus