Can Mystery Snail live with Swordtail?
Case-by-case. Watch group sizes, tank size, and feeding zones.
Why Mystery Snail and Swordtail Don't Make an Easy Pair
They can coexist, but you need to manage the setup carefully. The temperament combination (peaceful+semi-aggressive) can work, but you will need to watch them at feeding time for the first week.
Mystery Snail
Pomacea bridgesii
| Adult Size: | 2.0" |
| Temperament: | peaceful |
| Min Tank: | 5 gal |
| Temperature: | 68-84°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 | Mystery Snail | Swordtail | Overlap |
|---|---|---|---|
| Temperature | 68-84°F | 72-78°F | 6°F ✓ |
| pH | 7.0-8.0 | 7.0-8.0 | 1.0 ✓ |
Compatibility Breakdown
Temperament Match: peaceful + semi-aggressive. Semi-aggressive → watch territory and feeding.
⚠️ Size Predation Risk: Mystery Snail (2.0") vs Swordtail (5.0"). A 3.0" gap — the larger fish will view the smaller fish as food.
Score: 70.0/100 (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 72°F and 78°F.
- pH: maintain 7.0 – 8.0.
- Hiding spots: essential for Mystery Snail — 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:
LED filter for livebearer tanks
Explore Related Checks
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Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a peaceful individual Mystery Snail 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.