Guppy

Poecilia reticulata

Freshwater Captive bred worldwide Usually captive bred

A livebearer that breeds so easily that stocking numbers need planning from the first week. Males carry the colour and the show tails. Hard, slightly alkaline water suits it better than soft acidic water.

Also called: Barbados millions, Guppies.

4.5 cm adult length, drawn to scale. slim body.

Try it in the planner Opens a tank sized to its minimum with 1 fish added.

What it needs

Item	Value	Because
Adult length	4.5 cm	Used for the Space check: the tank must be long enough for the fish to turn round.
Smallest tank	40 L, at least 45 cm long estimated	The least water and floor length this species is kept in for good, as a single fish or smallest group.
Extra water per added fish	3 L estimated	What each further fish adds once the minimum is met.
Waste load	Class 1 of 5 estimated	How much waste an adult makes against its size. Feeds the Load check.
Temperature	22 to 28 C	Stock sharing a tank need overlapping ranges.
pH	7 to 8.2	Compared with tankmates in the Water check.
Hardness	GH 8 to 22, KH 4 to 12	Degrees of general and carbonate hardness.
Flow	Low	Low-flow fish are stressed in a strong current.
Light	Moderate	Matched to the lighting class on the needs sheet.
Group size	Single fish is fine	Not a schooling species.
Temperament	Peaceful	Not territorial.
Swims in	Upper water	Fish that use different levels share a tank more easily.
Lifespan	About 3 years	A fish is a long commitment.
Experience	Suits a first tank	A guide to how forgiving the species is of mistakes.
Jumps	Yes	Keep the tank covered.

Tags marked estimated are judged from the size and habits of the species rather than measured, so treat them as a sensible default.

Diet and tank layout

Guppy is an omnivore that swims in the upper water. It is safe with plants. Give it some cover.

Tankmates

Works with

Depends

Avoid

Compare any two fish on the compatibility page, or print the equipment for a stock on the needs sheet. How this is worked out: the method.