Molly and Pygmy Corydoras Compatibility Overview
Molly and Pygmy Corydoras can potentially coexist, but the combination requires careful attention. Their usable pH overlap is narrow and requires stable, tested water. A larger tank (minimum 55 gallons), dense planting, and close monitoring are essential.
| Factor | Molly | Pygmy Corydoras | Verdict |
|---|---|---|---|
| Temperature | 72โ82ยฐF | 72โ79ยฐF | โ 72โ79ยฐF |
| pH Range | 7.5โ8.5 | 6.0โ7.5 | โ ๏ธ 7.5โ7.5 (narrow) |
| Temperament | peaceful | peaceful | โ Compatible |
| Adult Size | 4 in | 1 in | โ 4ร difference |
| Min. Group | 3+ | 6+ | See below |
| Min. Tank Size | 55 gallons (for both species) | โ | |
Compatibility Positives
Caution Points
Species Profiles
Molly โ Poecilia sphenops
Hardy livebearers that prefer alkaline, hard water โ sometimes slightly brackish. Prolific breeders; peaceful community fish.
Pygmy Corydoras โ Corydoras pygmaeus
Tiny armoured catfish that school in open water as well as on the substrate. Peaceful with all non-aggressive species.
Frequently Asked Questions
Can Molly live with Pygmy Corydoras?
With significant caution and a larger tank. Molly and Pygmy Corydoras can potentially coexist, but the combination requires careful attention. Their usable pH overlap is narrow and requires stable, tested water. A larger tank (minimum 55 gallons), dense planting, and close monitoring are essential.
What tank size do I need for Molly and Pygmy Corydoras together?
A minimum of 55 gallons is recommended for keeping Molly and Pygmy Corydoras together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Molly and Pygmy Corydoras?
72โ79ยฐF โ inside Molly's 72โ82ยฐF and Pygmy Corydoras's 72โ79ยฐF.
Is a Molly aggressive toward a Pygmy Corydoras?
Molly is peaceful and Pygmy Corydoras is peaceful. No major aggression issues are expected between these species.
Related Compatibility Guides
Tank Size for Molly and Pygmy Corydoras
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 55 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 75 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 125 gal | Best when keeping larger schools or reducing territorial pressure. |