Compatibility Overview
Harlequin Rasbora and Three Spot Gourami 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 | Harlequin Rasbora | Three Spot Gourami | Verdict |
|---|---|---|---|
| Temperature | 72–81°F | 73–81°F | ✅ 73–81°F |
| pH Range | 5.5–7.5 | 6.5–7.5 | ✅ 6.5–7.5 |
| Temperament | peaceful | aggressive | ❌ Risk |
| Adult Size | 1.75 in | 2.4 in | ✅ Similar |
| Min. Group | 8+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Harlequin Rasbora — Trigonostigma heteromorpha
Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.
→ Full Harlequin Rasbora care guide
Three Spot Gourami — Aquarium species
The Three Spot Gourami is a peaceful and attractive addition to freshwater tanks. They are known for their vibrant coloration and peaceful demeanor. With their flowing tails and distinctive body spots, they add visual interest to the aquarium. Providing a well-planted tank with hiding spots is crucial for their well-being. As a beginner-friendly fish, they a
Frequently Asked Questions
Can Harlequin Rasbora live with Three Spot Gourami?
Yes, in a well-planned setup. Harlequin Rasbora and Three Spot Gourami 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 Harlequin Rasbora and Three Spot Gourami together?
A minimum of 55 gallons is recommended for keeping Harlequin Rasbora and Three Spot Gourami together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Harlequin Rasbora and Three Spot Gourami?
73–81°F
Is a Harlequin Rasbora aggressive toward a Three Spot Gourami?
Harlequin Rasbora is peaceful and Three Spot Gourami is aggressive. No major aggression issues are expected between these species.
Related Compatibility Guides
Compatibility score breakdown
The overall score is weighted across water chemistry, behavior, adult size, swimming zone, and social needs. A score is a planning aid—not a guarantee for individual fish.
| Factor | Score |
|---|---|
| Temperature | 100/100 |
| Ph | 100/100 |
| Temperament | 30/100 |
| Adult Size | 100/100 |
| Swim Zone | 68/100 |
| Social Needs | 92/100 |
Tank size scenarios
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. |