Otocinclus and Swordtail Compatibility Overview
Otocinclus and Swordtail can potentially coexist, but the combination requires careful attention. Their pH ranges overlap only partly, so aim for the shared band and keep it steady. A larger tank (minimum 55 gallons), dense planting, and close monitoring are essential.
| Factor | Otocinclus | Swordtail | Verdict |
|---|---|---|---|
| Temperature | 72โ82ยฐF | 65โ80ยฐF | โ 72โ80ยฐF |
| pH Range | 6.0โ7.5 | 7.0โ8.3 | โ ๏ธ 7.0โ7.5 (narrow) |
| Temperament | peaceful | peaceful | โ Compatible |
| Adult Size | 1.5 in | 5 in | โ ๏ธ 3.3ร difference |
| Min. Group | 4+ | 3+ | See below |
| Min. Tank Size | 55 gallons (for both species) | โ | |
Compatibility Positives
Caution Points
Species Profiles
Otocinclus โ Otocinclus spp.
Tiny algae-eating catfish that are peaceful with all species. Need established algae growth and biofilm; sensitive to ammonia.
โ Full Otocinclus care guide
Swordtail โ 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 Otocinclus live with Swordtail?
With significant caution and a larger tank. Otocinclus and Swordtail can potentially coexist, but the combination requires careful attention. Their pH ranges overlap only partly, so aim for the shared band and keep it steady. A larger tank (minimum 55 gallons), dense planting, and close monitoring are essential.
What tank size do I need for Otocinclus and Swordtail together?
A minimum of 55 gallons is recommended for keeping Otocinclus and Swordtail together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Otocinclus and Swordtail?
72โ80ยฐF โ inside Otocinclus's 72โ82ยฐF and Swordtail's 65โ80ยฐF.
Is a Otocinclus aggressive toward a Swordtail?
Otocinclus is peaceful and Swordtail is peaceful. No major aggression issues are expected between these species.
Related Compatibility Guides
Tank Size for Otocinclus and Swordtail
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 55 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 75 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 125 gal | Best when keeping larger schools or reducing territorial pressure. |