Molly pH: Ideal Water pH & Hardness
Ideal pH 7.5-8.5 · Hardness 15-30 dGH
The Molly prefers hard, alkaline water: pH 7.5-8.5 at 15-30 dGH. Test your tap water first — many keepers match this range with no adjustment.
Stability beats a perfect number. Chasing pH with chemicals causes dangerous swings; if your water is close, leave it. To gently soften and lower pH use RO water, driftwood or peat; to raise it use crushed coral or aragonite.
| pH | 7.5-8.5 |
|---|---|
| Hardness | 15-30 dGH |
Frequently asked questions
What pH is best for Molly?
pH 7.5-8.5 with hardness 15-30 dGH.
How do I adjust pH for a Molly?
Favor stability: match it naturally with driftwood or RO water to lower, or crushed coral to raise, rather than pH chemicals.
More on this species: Molly full care guide · tank size · temperature · pH & hardness · tank mates