Compatibility Overview
Chili Rasbora and Harlequin Rasbora 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 40-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Chili Rasbora | Harlequin Rasbora | Verdict |
|---|---|---|---|
| Temperature | 68–82°F | 72–81°F | ✅ 72–81°F |
| pH Range | 4.0–7.0 | 5.5–7.5 | ✅ 5.5–7.0 |
| Temperament | peaceful | peaceful | ✅ Compatible |
| Adult Size | 0.8 in | 1.75 in | ⚠️ 2.2× difference |
| Min. Group | 8+ | 8+ | See below |
| Min. Tank Size | 40 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Chili Rasbora — Boraras brigittae
Vivid red nano fish from Borneo blackwater habitats. Extremely small — only safe with fish too small to swallow them.
→ Full Chili Rasbora care guide
Harlequin Rasbora — Trigonostigma heteromorpha
Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.
Frequently Asked Questions
Can Chili Rasbora live with Harlequin Rasbora?
Yes, in a well-planned setup. Chili Rasbora and Harlequin Rasbora 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 40-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Chili Rasbora and Harlequin Rasbora together?
A minimum of 40 gallons is recommended for keeping Chili Rasbora and Harlequin Rasbora together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Chili Rasbora and Harlequin Rasbora?
72–81°F
Is a Chili Rasbora aggressive toward a Harlequin Rasbora?
Chili Rasbora is peaceful and Harlequin Rasbora is peaceful. No major aggression issues are expected between these species.