Can German Blue Ram live with Molly?
High risk due to water mismatch, aggression, or predation.
Why German Blue Ram and Molly Don't Make an Easy Pair
The size gap is 2.0" — German Blue Ram (2.5") and Molly (4.5"). A fish that fits in another fish's mouth will eventually end up there.
German Blue Ram
Mikrogeophagus ramirezi
| Adult Size: | 2.5" |
| Temperament: | peaceful |
| Min Tank: | 20 gal |
| Temperature: | 78-86°F |
| pH Range: | 5.0-7.0 |
Molly
Poecilia sphenops
| Adult Size: | 4.5" |
| Temperament: | peaceful |
| Min Tank: | 20 gal |
| Temperature: | 72-82°F |
| pH Range: | 7.0-8.0 |
Water Parameter Overlap
| Parameter | German Blue Ram | Molly | Overlap |
|---|---|---|---|
| Temperature | 78-86°F | 72-82°F | 4°F ✓ |
| pH | 5.0-7.0 | 7.0-8.0 | No overlap ✗ |
Compatibility Breakdown
Temperament Match: peaceful + peaceful. Both peaceful → minimal conflict.
⚠️ Size Predation Risk: German Blue Ram (2.5") vs Molly (4.5"). A 2.0" gap — the larger fish will view the smaller fish as food.
Score: 40/100 (GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Setup Requirements (for Both)
- Minimum tank: 20 gallons — sized for the larger fish in the pair.
- Temperature: keep it between 78°F and 82°F.
- pH: no shared range. One species will be outside its tolerance regardless of what you set.
- Hiding spots: essential for German Blue Ram — caves, plants, or driftwood to retreat when feeling stressed.
- Water changes: 25% weekly minimum. Two species mean double the bioload.
🔧 Tank Stocking Calculator
Enter tank size to calculate safe stocking levels:
Recommended Equipment
Based on tank size 20+ gallons:
Premium small pellet for delicate dwarf cichlids
Explore Related Checks
See what else works with these fish:
Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a peaceful individual German Blue Ram may act differently from its species average. Always observe, quarantine new arrivals for 2-4 weeks, and avoid overcrowding. If a pairing says CAUTION, start with a smaller group and a lid.