Compatibility Overview
Betta Fish and Swordtail can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges, and neither poses a major aggression risk to the other. A minimum 55-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Betta Fish | Swordtail | Verdict |
|---|---|---|---|
| Temperature | 76–82°F | 65–80°F | ✅ 76–80°F |
| pH Range | 6.5–7.5 | 7.0–8.3 | ⚠️ 7.0–7.5 (narrow) |
| Temperament | aggressive | peaceful | ❌ Risk |
| Adult Size | 3 in | 5 in | ✅ Similar |
| Min. Group | 1+ | 3+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Betta Fish — Betta splendens
Vibrant labyrinth fish from Southeast Asia. Males are highly territorial toward other bettas and fin-nippers; compatible with many peaceful species in large, planted tanks.
Swordtail — Xiphophorus hellerii
Hardy livebearer with a distinctive elongated lower tail fin in males. Peaceful community fish that tolerate a wide temperature range.
Frequently Asked Questions
Can Betta Fish live with Swordtail?
Yes, in a well-planned setup. Betta Fish and Swordtail can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges, and neither poses a major aggression risk to the other. A minimum 55-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Betta Fish and Swordtail together?
A minimum of 55 gallons is recommended for keeping Betta Fish and Swordtail together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Betta Fish and Swordtail?
76–80°F
Is a Betta Fish aggressive toward a Swordtail?
Betta Fish is aggressive and Swordtail is peaceful. Narrow temperature overlap (76–80°F) — keeping the tank at exactly 77–79°F is needed for both species.