Molly

Poecilia sphenops

Illustration of molly

The molly (Poecilia sphenops) is a peaceful fish that grows to about 4 inches and spends its time in mid-water. Keep at least 3 together, in a tank of 20 gallons or more, at 72–82°F and pH 7.5–8.5.

20 galsmallest tank
4″adult size
72–82°Ftemperature
7.5–8.5pH
3+group size
Peacefultemperament
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Good tankmates

Avoid

  • ✕Cardinal tetra: Molly and Cardinal tetra prefer different water (pH 7.5–8.5 vs 4.5–7).
  • ✕Ember tetra: Molly and Ember tetra prefer different water (pH 7.5–8.5 vs 5.5–7).
  • ✕Rummy-nose tetra: Molly and Rummy-nose tetra prefer different water (pH 7.5–8.5 vs 5.5–7).
  • ✕Chili rasbora: Molly and Chili rasbora prefer different water (pH 7.5–8.5 vs 4–7).
  • ✕Paradise fish: Paradise fish is aggressive and best kept alone.
  • ✕German blue ram: Molly and German blue ram prefer different water (pH 7.5–8.5 vs 5–7).
  • ✕Convict cichlid: Convict cichlid is aggressive and best kept alone.
  • ✕Oscar: Oscar is aggressive and best kept alone.

From TankCoach's own species data: common hobby guidance for adults, rounded. Individual fish vary. Not veterinary advice.