How long do Harlequin Rasboras live?
Harlequins are long-lived for small fish, commonly 5-8 years with good care. Stable water and a balanced diet are what carry them that far.
What do Harlequin Rasboras eat?
They take flake, micro-pellets, and small frozen/live foods like daphnia and brine shrimp. Overfeeding is the main diet error; feed small portions finished in two minutes, once or twice daily.
Tank size and water parameters
A 15-20 gallon (57-75 L) tank suits a school of 8-10. Target 72-81°F (22-27°C), pH 6.0-7.8, soft to moderate hardness, zero ammonia and nitrite, nitrate under 20 ppm. Keep in groups of 8+; plants and gentle flow suit them.
Common mistakes with Harlequin Rasboras
Usual errors: too small a group so they never school properly; mixing with fin-nippers or aggressive fish that stress them; and unstable water in a small tank from missed water changes.
Beginner mistakes to avoid
- Keeping a tiny group — harlequins need 8+ to form their signature school.
- Tank mates that nip or bully — they are too peaceful for rough company.
- Letting small-tank water swing — frequent partial changes keep them stable.
- Overfeeding — small, varied portions protect water quality.