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Variety of Black molly

Silver molly

Poecilia sphenops

One of 4 varieties of Poecilia sphenops · See all varieties →

FreshwaterBrackishFish

Silver molly (Poecilia sphenops)

Varieties · Poecilia sphenops

See all 4 →

Care at a glance

Temperature
70–82°F
21–28°C
pH
7.0–8.0
Adult size
4.7 in
12 cm
Minimum tank
24 gal
90 L
Temperament
Mostly peaceful
Social behavior
Social
Swim level
Middle
Diet
Omnivore
Difficulty
Easy
Breeding
Livebearer · Easy
Rarity
Very common
Family
Poeciliidae

Overview

The silver molly is the quiet option among molly color forms, showing the fish's outline rather than a pattern. It is easy to keep in a community tank with hard water.

Did you know

A silver molly's shine comes from crystals inside cells, not from the scales themselves. Mollies carry guanine platelets packed into iridophores. That is the same material scraped from fish scales to make the pearl essence used in cosmetics and nail polish.

Caring for the silver molly

Keep silver mollies in a small group in a tank of at least 24 gal (90 L). Plants, open swimming space and steady warmth suit them. They want hard, alkaline water at 70 to 82°F (21 to 28°C) and a pH of 7.0 to 8.0. A little salt in the water is tolerated and often appreciated.

Silver mollies graze algae and need real plant matter in their diet. Feed them a vegetable-based flake or pellet with some protein mixed in.

They are mostly peaceful and safe with other community fish. Keep more females than males to spread out the males' constant chasing. Females grow larger and rounder than males. Males carry a gonopodium, a modified anal fin used to fertilize females.

Silver mollies are livebearers and give birth to free-swimming young instead of laying eggs. They breed easily, so expect fry.

Good to know

The silver molly's color comes from subtraction, not addition. Hobby references describe the form as having every pigment but the silver bred out. That leaves the guanine-backed iridophores that already give mollies their shine. That is why the fish looks metallic rather than white. Albino fish also lack pigment, but they lose eye color with it, and a silver molly keeps dark eyes. It ships plainly as Silver Molly, usually short-finned, and batches differ in how much olive sheen carries over the back.

In the wild

The silver molly is a selection line on mixed trade stock, since the short-finned and sailfin species have been crossed for decades. A shop molly is rarely one clean species. Unlike most fancy forms, the silver sits close to the wild coloration. Some shops present it as the wild-type molly, which is close but not exact. Wild fish carry extra speckling and color over the same silvery ground. The line has no recorded originator.

Weekly picks

Tank mates

The silver molly is a mostly peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

Is a silver molly a different species from the black molly?

No. A silver molly is a variety of the black molly, Poecilia sphenops, and it wants the same tank, water and food as the species.

What size tank does a silver molly need?

A silver molly needs at least 24 gal (90 L). It spends most of its time in the middle.

What does a silver molly eat?

A silver molly grazes algae and needs real plant matter. Feed it a vegetable-based flake or pellet with some protein mixed in.

How big does a silver molly get?

An adult silver molly reaches about 4.7 in (12 cm).

How can you tell a male silver molly from a female?

Males carry a gonopodium, a modified anal fin they use to fertilize females. Females grow larger and rounder than males.

How does a silver molly breed?

A silver molly is a livebearer and gives birth to free-swimming young rather than laying eggs. It breeds easily, so expect fry.

Related species