Compatibility Overview
Guppy 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 55-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Guppy | Harlequin Rasbora | Verdict |
|---|---|---|---|
| Temperature | 72–82°F | 72–81°F | ✅ 72–81°F |
| pH Range | 6.8–8.5 | 5.5–7.5 | ⚠️ 6.8–7.5 (narrow) |
| Temperament | peaceful | peaceful | ✅ Compatible |
| Adult Size | 2.5 in | 1.75 in | ✅ Similar |
| Min. Group | 3+ | 8+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Guppy — Poecilia reticulata
Hardy and colourful livebearers. Males' long flowing tails make them targets for fin-nipping species. Very prolific breeders.
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 Guppy live with Harlequin Rasbora?
Yes, in a well-planned setup. Guppy 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 55-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Guppy and Harlequin Rasbora together?
A minimum of 55 gallons is recommended for keeping Guppy and Harlequin Rasbora together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Guppy and Harlequin Rasbora?
72–81°F
Is a Guppy aggressive toward a Harlequin Rasbora?
Guppy is peaceful and Harlequin Rasbora is peaceful. Limited pH overlap (6.8–7.5) — maintain pH carefully within this narrow window.