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fishbeginner
Harlequin Rasbora
Trigonostigma heteromorpha
A copper-red schooling fish with a black triangle — one of the calmest community fish there is.
1.75 in5–8 years
Habitat
Enclosure
10 gal minimum · schools of 8+
Temperature
72–77°F
Humidity / Water
Freshwater · pH 5.5–7.5
Heating & lighting
Gentle heater, dim lighting, and planted areas. Very tolerant of different water chemistry — a forgiving beginner schooler.
Diet
Feed these
- Micro pellets
- Crushed flake food
- Frozen daphnia
- Frozen baby brine shrimp
Never feed
- Large pellets (tiny mouths)
- Fin-nipping tank mates
- Water below 68°F
Feed small pinches twice a day. A big group in a planted tank shows off their color far better than pairs.
Cohabitation
Can live with
Neon tetras Corydoras catfish Betta — in large calm tanks Cherry barbs Other harlequin rasboras — schools of 8+
Never house with
Oscar — they're food Angelfish — predation and nipping risk Tiger barbs
Peaceful mid-level schoolers that mix with nearly anything calm. The bigger the school, the better they look.
