Can Molly Live With Oscar?
Molly and Oscar are NOT compatible tank mates.
Detailed Analysis
Temperature
✓ Compatible
Good temperature overlap at 74–81°F.
pH
✓ Compatible
Good pH overlap at 7.0–7.5.
Size
⚠ Use Caution
Significant size difference (14" vs 4"). Oscar may bully or stress Molly.
Temperament
✗ Not Compatible
Molly (peaceful) is not compatible with Oscar (aggressive). Aggression or stress is very likely.
Swim Level
⚠ Use Caution
Both fish occupy the middle level and Oscar is territorial. Provide plenty of space and hiding spots.
Trait Conflict
✗ Not Compatible
Oscar is a predator and may eat Molly.
Trait Conflict
⚠ Use Caution
Molly may prefer brackish water conditions, which Oscar cannot tolerate long-term.
Tank Requirements
Minimum tank size for this combination: 75 gallons
| Parameter | Molly | Oscar |
|---|---|---|
| Temperature | 72–82°F | 74–81°F |
| pH | 7–8.5 | 6–7.5 |
| Max Size | 4" | 14" |
| Temperament | Peaceful | Aggressive |
| Swim Level | Middle | Middle |
| Min Tank | 20 gal | 75 gal |
Check More Combinations
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