Overview
The Common Molly (Poecilia sphenops) is a beginner freshwater species known for its black (also orange, white, dalmatian variants) coloration. Tolerates brackish water. Mid.
Origin & Appearance
Origin: Central America.
Colors: Black (also Orange, White, Dalmatian variants).
Body Shape: Fusiform (torpedo/streamlined). Typical adult dimensions: 12.0 x 2.2 x 3.6.
Sexual Dimorphism: Moderate; males have gonopodium, larger dorsal fin.
Tank & Water Requirements
| Min Tank Size | 20 gallons |
| Temperature | 72–82°F |
| pH Range | 7–8.5 |
| Water Hardness (GH) | 10-25 |
| Bioload | medium |
| Oxygen Demand | low |
| Plant Safe | mostly |
| Aquarium Position | Mid |
Behavior & Activity
Steady mid-level cruiser; glides smoothly with gentle tail sweeps; occasionally grazes algae off surfaces; calm continuous movement
Speed: 40/100Aggression: 2/10diurnalSchooling (4+)
Breeding
Easy; livebearer
Common Diseases
💊 Ich💊 shimmies (low salt/mineral)
Expert Notes
Tolerates brackish water