Guppy

Poecilia reticulata

Livebearers

One of the most iconic and widely kept aquarium fish. Renowned for their incredible colors, hardiness, and prolific breeding. As livebearers, they give birth to fully formed, free-swimming fry. Males constantly pursue females for mating; therefore, a ratio of at least 2 females per male is strongly recommended to disperse stress.

At a Glance

Adult Size5 cm
Body ShapeFusiform
Growth RateFast
TemperamentPeaceful
Water TypeBrackish Tolerant
Flow PreferenceLow
Waste OutputHigh
StockingGroup of 3+

Tank Requirements

Minimum Volume38 L
Minimum Length45 cm
FlowLow
Water TypeBrackish Tolerant
Must-Haves in the Tank
Plants - Densely coveredPlants - Floating

Water Parameters

Temperature2228°C
pH78.5
Hardness830 dGH

Temperament & Compatibility

Aggression LevelPeaceful
1/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least3 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerFry Predator

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Male (Fancy)

Males are significantly smaller but boast spectacular colors and large, flowing fins. They are extremely active and will relentlessly court females. Can be kept in a 'bachelor' (male-only) tank to prevent breeding.

Differs in 2 traits from base species

Also known as: Male Guppy, Cobra, Delta Tail, Mosaic

Adult Size3.5 cm
Behavior Traits
Hyperactive / Fast SwimmerFry PredatorLong Finned (Nipper Target)

Female

Females are larger, thicker, and generally less colorful than males (though modern strains have colorful tails). They possess a distinct dark 'gravid spot' near the anal fin and can store sperm for months, dropping fry every 21-30 days.

Differs in 1 trait from base species

Also known as: Female Guppy, Breeder

Adult Size6 cm

Guppy Care Summary

The Guppy, scientifically known as Poecilia reticulata, belongs to the Livebearers family group. Adults reach a maximum size of approximately 5 cm and have a fusiform body shape with a fast growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a high level of biological waste.

To thrive, the Guppy requires a brackish tolerant aquarium with a minimum volume of 38 litres and a tank length of at least 45 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 78.5 and a general hardness of 830 dGH. A low water flow is preferred. To replicate their natural habitat, the tank should include plants - densely covered and plants - floating.

This species should be kept in groups of at least 3 to reduce stress and encourage natural behaviour. This species is available in 2 varieties: Male (Fancy) and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.


Similar Species

Endler's Livebearer

Poecilia wingei

Livebearers
2.5 cm Peaceful

A tiny, vibrant, and highly active livebearer closely related to the Guppy. Males display intense, neon colors and patterns, while females are larger and plainly colored. They are prolific breeders and require hard, alkaline water to thrive.

Goldfish (Comet / Common)

Carassius auratus

Goldfish & Koi
30 cm Peaceful

One of the most commonly kept and misunderstood fish in the hobby. Single-tailed goldfish (Comets, Commons, Shubunkins) are fast-growing, highly active coldwater fish that produce enormous amounts of waste. They are best suited for ponds or massive aquariums. They will uproot plants, sift substrate constantly, and eat anything that fits in their mouths.

Platy

Xiphophorus maculatus

Livebearers
6 cm Peaceful

A quintessential community fish known for its durability and massive variety of colors. Native to Central America, Platies are livebearers, meaning they give birth to free-swimming fry. They are peaceful, active grazers that require hard, alkaline water to thrive. They are excellent for beginners but breed prolifically.

Paradise Fish

Macropodus opercularis

Anabantoids
10 cm Aggressive

One of the first ornamental fish in the hobby (pre-dating the Goldfish in Europe). Paradise Fish are stunning, hardy, subtropical Anabantoids. However, they are notoriously aggressive, often exceeding the aggression of Bettas. They are cold-tolerant and thrive in unheated indoor aquariums, but they will readily attack smaller tank mates, eat fry, and fight conspecifics to the death.

Zebra Danio

Danio rerio

Cyprinids
5 cm Mostly Peaceful

One of the most robust and active aquarium fish available. Native to South Asia, they are a model organism in science due to their genetics. They are extremely active top-level swimmers that must be kept in schools to prevent stress and fin-nipping. They prefer cooler, oxygen-rich water with a current.

Peacock Gudgeon

Tateurndina ocellicauda

Gobies & Gudgeons
6 cm Peaceful

A stunning, peaceful freshwater sleeper goby from Papua New Guinea. Known for their vibrant blue, red, and yellow colors, they are excellent nano-tank inhabitants. They are not true gobies (they lack fused pelvic fins) and are exclusively freshwater. They prefer slow-moving water, dense vegetation, and small caves (like PVC pipes or smooth stones) for spawning.