Harlequin Rasbora and Swordtail Compatibility Overview
Harlequin Rasbora and Swordtail can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Both species are peaceful, and neither poses a major aggression risk to the other. A minimum 75-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Harlequin Rasbora | Swordtail | Verdict |
|---|---|---|---|
| Temperature | 72โ81ยฐF | 65โ80ยฐF | โ 72โ80ยฐF |
| pH Range | 5.5โ7.5 | 7.0โ8.3 | โ ๏ธ 7.0โ7.5 (narrow) |
| Temperament | peaceful | peaceful | โ Compatible |
| Adult Size | 1.75 in | 5 in | โ ๏ธ 2.9ร difference |
| Min. Group | 8+ | 3+ | See below |
| Min. Tank Size | 75 gallons (for both species) | โ | |
Compatibility Positives
Caution Points
Species Profiles
Harlequin Rasbora โ Trigonostigma heteromorpha
Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.
โ Full Harlequin Rasbora 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 Harlequin Rasbora live with Swordtail?
Yes, in a well-planned setup. Harlequin Rasbora and Swordtail can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Both species are peaceful, and neither poses a major aggression risk to the other. A minimum 75-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Harlequin Rasbora and Swordtail together?
A minimum of 75 gallons is recommended for keeping Harlequin Rasbora and Swordtail together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Harlequin Rasbora and Swordtail?
72โ80ยฐF โ inside Harlequin Rasbora's 72โ81ยฐF and Swordtail's 65โ80ยฐF.
Is a Harlequin Rasbora aggressive toward a Swordtail?
Harlequin Rasbora is peaceful and Swordtail is peaceful. No major aggression issues are expected between these species.
Related Compatibility Guides
Tank Size for Harlequin Rasbora and Swordtail
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 75 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 125 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 150 gal | Best when keeping larger schools or reducing territorial pressure. |