Molly
Poecilia sphenops
Family: Poeciliidae • Origin: Central America
Mollies are large livebearers available in black, gold, dalmatian, and sailfin varieties. They prefer hard alkaline water and even tolerate brackish.
Min Tank
20 gal
Max Size
4.5"
Temperature
72-82°F
pH
7-8.5
Lifespan
4 years
School Size
3+
Swim Level
middle
Hardness
15-30 dGH
peacefulbeginneromnivoreschooling
Care Tips
- • Prefers very hard alkaline water
- • Can live in brackish water
- • Larger than guppies — need 20+ gal
- • Prolific breeders
- • Natural algae grazer
Feeding: Flakes, algae wafers, blanched vegetables, spirulina.
Compatibility Notes: Prefers very hard water. Can tolerate brackish conditions. Needs more space than guppies.
Tank Setup & Water Parameters
Tank Requirements
- Minimum Tank Size
- 20 gallons
- Recommended Tank Size
- 30 gallons
- Swimming Level
- middle
- Minimum School Size
- 3+ fish
Water Parameters
- Temperature
- 72–82°F
- pH Range
- 7–8.5
- Hardness (dGH)
- 15–30
- Water Type
- freshwater
Behavior & Temperament
- Temperament
- peaceful
- Aggression Level
- 2/5
- Schooling
- Yes
- Territorial
- No
- Fin Nipper
- No
- Predatory
- No
- Diet Type
- omnivore
- Growth Rate
- fast
Prefers very hard water. Can tolerate brackish conditions. Needs more space than guppies.
Breeding
- Breeding Type
- live bearer
- Breeding Difficulty
- easy
- Lifespan
- 4 years
Ideal For
20 galloncommunitybeginners
Compatible Tank Mates
View all →
Black Neon Tetra
Hyphessobrycon herbertaxelrodi
73-81°FpH 5.5-7.510+ gal
peacefulschooling 6+1.6"
Serpae Tetra
Hyphessobrycon eques
72-82°FpH 6-7.520+ gal
semi-aggressiveschooling 6+1.75"
Black Skirt Tetra
Gymnocorymbus ternetzi
70-82°FpH 6-7.515+ gal
peacefulschooling 5+3"
Congo Tetra
Phenacogrammus interruptus
75-81°FpH 6-7.530+ gal
peacefulschooling 6+3.5"
Guppy
Poecilia reticulata
72-82°FpH 6.8-7.810+ gal
peacefulschooling 3+2.5"
Endler's Livebearer
Poecilia wingei
72-82°FpH 6.5-85+ gal
peacefulschooling 3+1.5"
Similar Species
Platy
Xiphophorus maculatus
70-80°FpH 7-810+ gal
peacefulschooling 3+3"
Balloon Molly
Poecilia sphenops var.
72-82°FpH 7-8.510+ gal
peacefulschooling 3+3"
Variatus Platy
Xiphophorus variatus
68-77°FpH 7-810+ gal
peacefulschooling 3+2.5"
Limia Nigrofasciata
Limia nigrofasciata
72-82°FpH 7-8.510+ gal
peacefulschooling 4+2.5"