Black Molly

Poecilia sphenops

Animalia›Chordata›Actinopterygii

Variety of Molly · black

📍 Central America

A classic and popular molly variety selectively bred for entirely jet-black coloration across the body and fins. It is hardy, peaceful, and one of the most beginner-friendly livebearers, tolerating a wide range of water conditions and benefiting from a small addition of aquarium salt.

Size3"

Min Tank20g

School3+

peaceful

Zonemid

Care Guide

Diet

Black Mollies are omnivorous and thrive on a varied diet of high-quality flake foods, sinking pellets, and vegetable matter like blanched spinach or algae wafers. Feed small amounts once daily, only what they can consume in 2-3 minutes. Supplement occasionally with frozen foods such as brine shrimp or daphnia to promote color and overall health.

Behavior

Black Mollies are peaceful, active swimmers that spend most of their time in mid-water zones, though they occasionally visit the surface and bottom. They are social fish that do best in small groups of 3 or more and display minimal aggression toward other peaceful species. Males may chase females during breeding season, but this is rarely harmful.

Breeding

Black Mollies breed readily in captivity and are prolific livebearers that produce 20-100 fry every 4-6 weeks under good conditions. Females give birth to fully-formed, free-swimming young without requiring special breeding tanks, though fry survival is higher if dense plants are provided for shelter. Breeding is easy and happens naturally in established community tanks.

Tank Mates

Guppy

Similar peaceful temperament, identical water parameters, and compatible size make them ideal companions

excellent

Platy

Fellow livebearer with matching care requirements and peaceful nature; can interbreed but offspring are sterile

excellent

Neon Tetra

Small, peaceful schooling fish that coexist well; slightly prefer cooler temps but overlap is acceptable

good

Gold Mystery Snail

Peaceful invertebrate that benefits from the same water conditions and helps control algae

excellent

Dwarf Gourami

Peaceful mid-water dweller with compatible temperature range; generally non-aggressive toward mollies

good

Common Diseases

Fin Rot

Symptoms

Frayed, disintegrating fins; white or black edges on fin tissue; lethargy

Treatment

Perform 25% water changes every 2-3 days, improve water quality, maintain temperature at 76-78°F, and consider antibacterial medication if severe

Ich (Ick)

Symptoms

White spots covering body and fins; excessive scratching against objects; rapid breathing

Treatment

Raise temperature gradually to 82°F, add aquarium salt (1 teaspoon per 5 gallons), and treat with ich medication for 7-10 days while maintaining good aeration

Velvet Disease

Symptoms

Fine golden or rust-colored dust on body; clamped fins; loss of appetite; rapid gill movement

Treatment

Dim lighting, raise temperature to 80-82°F, perform daily 25% water changes, and treat with copper-based medication or formalin following product instructions