Fish care
Molly Fish: Complete Care Guide
Last updated: May 2026
Summary
Structured care sheet for Molly (Poecilia sphenops). Validate every purchase with the free aquarium stocking calculator, parameter testing habits, and the species database table.
- Cross-check length and temperature against the species explorer.
- Track nitrate drift weekly once the tank has cycled.
- Refer to the species hub for long-form tank mate essays.
Max size12 cm / 4.7in
Temperature22-28°C / 72–82°F
pH range7–8.5
Min tank size80 L / 21 US gal
Care levelEasy
TemperamentPeaceful
DietOmnivore
Swim zoneVaries
Salinity options
Many molly lines tolerate light brackish conditions; if your fish ship from brackish farms, full freshwater without acclimation can invite fungus. Match the seller’s salinity on arrival, then adjust slowly if you prefer fresh long term.
Fin nipping among males
Competition spikes in overcrowded tanks—give females cover and keep sex ratios sane to reduce constant chase energy.
See tank mate combinations tuned to temperament overlap.
Browser calculator stays free. The app only matters if you want several tanks, photos, and test history on your phone.
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