Species Profile
Harlequin Rasbora
Trigonostigma heteromorpha
Rasboraspeaceful
Adult size
2″
Minimum tank
15 gal
Temperature
72–81°F
pH
6–7.5
Schooling
Group of 6+
Water level
mid
Diet
Flake, small pellets
Notes
Classic peaceful schooler from southeast Asian peat swamps, recognizable by the black wedge on the rear half. Hardy enough for beginners but happiest in soft acidic blackwater. Group of 8+ produces a noticeable shimmer.
Compatible Tankmates
Best tank mates for Harlequin Rasbora
Every species below passes the compatibility engine when paired with Harlequin Rasborain a suitably sized tank. Verdicts come from the same rules the builder uses — click a card to see that species' own care profile and its tank mates in turn.
Neon Tetra
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Cardinal Tetra
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Rummynose Tetra
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Zebra Danio
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Fancy Guppy
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Endler's Livebearer
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Platy
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Molly
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Swordtail
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Male Betta
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Dwarf Gourami
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Honey Gourami
ExcellentPeaceful pairing — temperament, water parameters, and size all line up.
Photo: Vassil / Wikimedia Commons · Source · CC0-1.0