Poeciliidae

Gold Molly

Poecilia sphenops

A form of:Molly sphenops

In the trade this fish is sold as Molly Gold, or gold molly; it is often called yellow molly as well. The gold molly is a cultivated form, not found in nature. It was developed by crossing popular Poecilia species such as Poecilia velifera, Poecilia latipinna, and Poecilia sphenops, along with their hybrids, to achieve the distinctive coloration.

Tank
from 150 L (40 gal)
Temperature
21 – 26 °C (70 – 79 °F)
Size in aquarium
8 – 12 cm (3.1 – 4.7 in)
Acidity
pH 7–8.5
Natural rangeRange on the map
  • Central America area
  • Colombia
  • Cook Islands
  • Curaçao
  • El Salvador
  • Honduras
  • Mexico
  • Nicaragua
  • Venezuela

Tank conditions

Plan the tank stocking
Temperature
21 – 26 °C (70 – 79 °F)
Water pH
Neutral (7) – Slightly alkaline (8.5)
Water dH
Hard (15) – Very hard (30)
Water salinity
low (3–5 g/L)
Size in aquarium
8 – 12 cm (3.1 – 4.7 in)
Lifespan
4 years
Temperament
Peaceful (regular)
Toward small fish
not a predator
Required aquarium volume
from 150 L (40 gal)
Lighting
any
Substrate
any (no restrictions)
Water flow
weak
Swimming level
near the surface
Feeding
Mixed diet meat + plant-based
Keeping
Mixed solitary / pair / group
Jumping
high a tight-fitting lid is essential
  • Lifespan. A lifespan to expect under good care, not a measured value: it depends heavily on tank volume, water quality and diet — and for selectively bred forms, on their origin as well.
  • Toward small fish. Based on the Predators category in the catalog or the temperament in the species parameters. “A risk to small fish” means the species is not a predator by habit, yet will swallow any fish that fits in its mouth.
  • Required aquarium volume. This is a husbandry recommendation, not a measured value: the volume depends on the keeping mode (mixed (solitary / pair / group)), footprint, decor and tank mates.

Care and keeping

Description

The gold molly is a cultivated form created by crossing different Poecilia species. These fish have a bright, solid yellow or golden body colour; spots or patches of other colours are not typical of a pure line. Body and fin shape varies depending on the parent species, and may include lyretail varieties and fish with enlarged dorsal fins. The sexes differ visibly: males are slimmer and have a specialised reproductive organ called a gonopodium, while females are larger with a rounded belly.

Habitat

The parent species, such as Poecilia sphenops, inhabit freshwater and brackish waters in Central and North America, from the southern United States through Colombia and Venezuela. They often live in river mouths and coastal zones. In nature they prefer densely vegetated areas that provide shelter, and waters with stable conditions, though they are adaptable to a range of environments.

Behavior and Compatibility

Gold mollies are peaceful and active. In a small tank, keep more females than males so the males do not pester them. They get along well with other fish of similar size. The one exception is large, aggressive predators — do not keep them together.

Care and Maintenance

Keeping gold mollies is much like keeping other molly varieties. For a group of 3–4 fish, a spacious tank of 100–150 litres is ideal. Maintain a temperature of 23–28°C, keep the water clean, and monitor water pH at 7–8 and water dH at 10–20. Plant the tank densely with aquatic plants. Gold mollies do well in slightly brackish water, so this is an option if it suits other tank mates. Long-term health depends on regular tank maintenance, including waste removal and water changes, a well-balanced diet, and compatible tank mates.

Diet

Gold mollies are omnivorous and need a varied diet that must include plant material every day. Commercial flakes or pellets designed for mollies are the most convenient option. Be aware that delicate plants may be damaged by these fish; choose fast-growing, hardy species for the tank.

Breeding and Reproduction

If you have a breeding pair, fry will almost certainly appear. The young are born fully formed and ready to eat immediately. Adult fish do not care for their young and will eat them if they get the chance.

Diseases

This species is sensitive to sudden swings in temperature and water quality, which can weaken immunity and lead to infection. Gas bubble disease can occur if tap water is not left to stand before use, and chilling causes colds. To prevent problems, maintain a steady temperature, provide good filtration and aeration, and keep the substrate clean with regular water changes.

How to choose

When choosing fish, look for active individuals with no visible damage, scale cloudiness, or signs of poor condition. Avoid fish with clamped fins, unusual behaviour (lethargy or restlessness), or body deformities. Buy from reliable sources that maintain proper stocking densities and tank hygiene.

Compatibility

There are no pair reviews for this species yet — check tankmates in the matcher.

All tankmates

Plants and this fish

Matching water does not mean the plant will stay intact.

Frequently asked questions

The essentials: size, tank volume, water parameters and care

How big does Gold Molly get?

An adult reaches 8–12 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.

What size aquarium does Gold Molly need?

The recommended volume is 150 L. A smaller tank speeds up nitrate build-up and raises stress levels.

What water parameters does Gold Molly need?

Temperature 21–26 °C, pH 7–8.5, hardness 15–30 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.

How long does Gold Molly live?

Around 4 years when kept properly. Lifespan depends directly on tank volume, water quality and a varied diet.

Is Gold Molly aggressive?

Temperament: peaceful (regular). Keep this in mind when choosing tank mates.

How many Gold Molly should be kept together?

Recommended setup: mixed (solitary / pair / group). Ignoring this is a common cause of stress and disease.

What does Gold Molly eat?

Diet type: mixed diet (meat + plant-based). Feed small portions that are finished within a couple of minutes — overfeeding does more harm than underfeeding.

What is the scientific name of Gold Molly?

The scientific name of the species is Poecilia sphenops, family Poeciliidae. It also appears in the literature as: Gambusia modesta, Gambusia plumbea, Lembesseia parvianalis.

Similar fishes

Matched by family, categories and overlapping keeping conditions

Balloon Molly

Balloon Molly

Poecilia sphenops

Poeciliidae

The Balloon Molly, also known as the Balloon Molly, is called the Balloon Molly in English-speaking trade. This common name is given to selective breeding forms obtained by breeding based on Poecilia sphenops, Poecilia…

Black and White Molly

Black and White Molly

Poecilia sphenops

Poeciliidae

The Black and White Molly is a collective name for several selectively bred forms distinguished by their characteristic body colouring dominated by black and white tones. Examples of these forms include the Dalmatian…

Black and Yellow Molly

Black and Yellow Molly

Poecilia sphenops

Poeciliidae

The Black and Yellow Molly, also known as Gold Dust Molly, takes its names from English trade names: Gold and Black Molly Fish and Gold dust molly. These names refer to a colour form of Poecilia sphenops distinguished…

Black Molly

Black Molly

Poecilia sphenops

Poeciliidae

The black molly, often simply called Black Molly, is apparently a selectively bred colour variant of the common molly, Poecilia sphenops. Some experienced breeders argue instead that it descends from Poecilia latipinna.…

Other scientific names and conservation status

Other scientific names
Gambusia modesta, Gambusia plumbea, Lembesseia parvianalis, Mollienesia altissima, Mollienesia macrura, Mollienesia pallida
Categories
Livebearers
Conservation status
Least concernLC