Guppy

Overview

The Guppy (Poecilia reticulata) is one of the most popular and easiest tropical freshwater fish - colourful, hardy, peaceful, and famously prolific. Often the first fish for new aquarium keepers and a staple of community tanks.

Natural History

Native to South America (Trinidad, Venezuela, Guyana, Brazil). Livebearing - produces live young instead of eggs. Established invasive populations worldwide.

Appearance

Adults: females 4-6 cm, males 3-4 cm. Males have brilliant colours and long flowing tails; females are larger but plainer.

Hundreds of strain types: cobra, snakeskin, mosaic, tuxedo, half-black, albino, and many more.

Temperament & Tankmates

Peaceful. Excellent in community tanks with other small peaceful fish. Avoid:

• Fin-nippers (tiger barbs, some tetras).
• Large predators.

Mix with: small tetras, corydoras, otocinclus, peaceful livebearers (platy, molly).

Tank Size & Setup

Minimum: 40 L (10 gallon) for a group of 5-7. Larger preferred.

Keep at least 3 - guppies are schooling/grouping fish.

If breeding is not desired, keep all-male or all-female groups. Mixed-sex groups produce non-stop fry - females can store sperm and produce multiple broods from one mating.

Water Parameters

• Temperature: 22-28°C.
• pH: 6.8-7.8 (tolerates wide range).
• Hardness: moderate to hard.

Diet

Omnivore. Wild guppies feed on algal remains, diatoms, invertebrates, zooplankton, detritus, plant fragments and aquatic insect larvae (Wikipedia). In the tank, give a tropical fish flake or micro pellet as the staple and add other foods for balance and enrichment, as the RSPCA advises.

Feed two or three times a day, as much as the fish eat within two to five minutes. Underfeeding is safer than overfeeding, because fish suffer more from poor water quality than from a lack of food (RSPCA).

Health & Lifespan

1.5-3 years.

Common concerns:

• Inbreeding decline - modern Guppy strains often weak; quality from reputable breeders fares better.
• Ich.
• Fin rot.
• Tuberculosis (rare).
• Dropsy.

Pros & Cons

Pros: brilliant colours, peaceful, easy to keep, breed easily, ideal for beginners. Cons: short lifespan, fry production constant in mixed-sex tanks, weak inbred strains.