Livebearers · Poecilia

Molly

Poecilia sphenops · Coastal rivers, Mexico to Colombia

Photo: Dnoerholm, CC BY-SA 4.0, via Wikimedia Commons

The Molly (Poecilia sphenops) is a freshwater fish from Coastal rivers, Mexico to Colombia, where it lives in brackish estuary habitat. Adults reach about 8 cm (3.1 in). Keep it at 22–28 °C (72–82 °F) and pH 7.5–8.5, in calm water. It is peaceful and does best in a group of 3 or more. It eats most foods: flakes, small pellets and frozen foods.

At a glance

Water temperature

22–28 °C 72–82 °F

7.5–8.5 hard, alkaline water

Adult size

8 cm 3.1 in

Swims

Mid-water and top mostly in open water

Keep together

3 or more a shoal feels safe

Current

Calm still or slow water

Food

Eats most foods

Temperament

Peaceful

≈ Every value here is an estimate from typical hobby ranges. We're checking them against sources.

Where it comes from

Home water

Coastal rivers, Mexico to Colombia

Lives in brackish estuary habitat.

The dot marks where it's collected. Home from iNaturalist native sightings (56). Map: Natural Earth.

Tank mates

Checked against a roomy 300 L planted tank with low flow and plenty of caves. Your own tank may change the answer: try it in Your tanks.

Good together

Keep apart

Aggressive and will eat the molly

Oscar
Want fast, strong current

Angelicus L136 Big white spot L142 Blue phantom L128 Butterfly hillstream loach Colombian zebra L129
Need a different pH

Cardinal tetra Chili rasbora

In the hobby

In stock now

Not in stock at any store we track.

Tanks with this fish

No shared tanks have this fish yet. Share yours from Your tanks.

From keepers

Notes appear here when a keeper shares a tank with this fish and writes about it.

Questions keepers ask

How big does a Molly get?

About 8 cm (3.1 in) as an adult.

What temperature does a Molly need?

22–28 °C (72–82 °F).

What pH does a Molly need?

pH 7.5–8.5.

Does a Molly need to be kept in a group?

Yes. Keep at least 3.

Is the Molly aggressive?

No. It is peaceful with fish that suit the same water.

What does a Molly eat?

It eats most foods: flakes, small pellets and frozen foods.

Where does the Molly come from?

Coastal rivers, Mexico to Colombia.

What fish can live with a Molly?

Good tank mates include Candy stripe (L015), Leopard frog (L134), Amano shrimp, Boeseman's rainbowfish, Bolivian ram.

All the numbers

Temperature min (°C)	22	Estimate
Temperature max (°C)	28	Estimate
pH min	7.5	Estimate
pH max	8.5	Estimate
Adult size (cm)	8	Estimate
Flow	Low	Estimate
Habitat	brackish	Estimate
Smallest happy group	3	Estimate
Temperament	Peaceful	Estimate
Diet	Omnivore	Estimate
Typical price min (CAD)	3	Estimate
Typical price max (CAD)	7	Estimate

Some values are estimates from typical hobby ranges and haven't been checked against a source yet.