Fish care
Harlequin Rasbora: Complete Care Guide
Last updated: May 2026
Summary
Structured care sheet for Harlequin rasbora (Trigonostigma heteromorpha). Validate every purchase with the free aquarium stocking calculator, parameter testing habits, and the species database table.
- Cross-check length and temperature against the species explorer.
- Track nitrate drift weekly once the tank has cycled.
- Refer to the species hub for long-form tank mate essays.
Max size5 cm / 2.0in
Temperature22-27°C / 72–81°F
pH range6–7.5
Min tank size60 L / 16 US gal
Care levelEasy
TemperamentPeaceful shoaling
DietOmnivore
Swim zoneVaries
Wedge pattern cues
The black wedge should read crisp on healthy fish; blurred edges sometimes precede velvet or slim coat issues - confirm with side lighting before dumping chemicals.
Midwater peace
They stay off the substrate drama - pair them with calm bottom fish rather than territorial cave cichlids that blast through the water column.
See tank mate combinations tuned to temperament overlap.
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