Can Molly live with Swordtail?
🟢 GOOD
These two species are usually compatible in community tanks.
Molly
Poecilia sphenops
| Adult Size: | 4.5" |
| Temperament: | peaceful |
| Min Tank: | 20 gal |
| Temperature: | 72-82°F |
| pH Range: | 7.0-8.0 |
Swordtail
Xiphophorus helleri
| Adult Size: | 5.0" |
| Temperament: | semi-aggressive |
| Min Tank: | 20 gal |
| Temperature: | 72-78°F |
| pH Range: | 7.0-8.0 |
Water Parameter Overlap
| Parameter | Molly | Swordtail | Overlap |
|---|---|---|---|
| Temperature | 72-82°F | 72-78°F | 6°F ✓ |
| pH | 7.0-8.0 | 7.0-8.0 | 1.0 ✓ |
Why GOOD?
Temperament Match: peaceful + semi-aggressive. Semi-aggressive → watch territory and feeding.
Score: 100.0/100 (GOOD threshold: GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Stocking Calculator
Enter tank size to calculate safe stocking levels:
Recommended Equipment
Based on tank size 20+ gallons:
Tetra Whisper Internal Filter — $19.99
Quiet internal filter for 20-gallon tanks
Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies. Always observe, quarantine new arrivals for 2-4 weeks, and avoid overcrowding.