Flag Tetra tank mates
Hyphessobrycon heterorhabdus
5 rated pairings from the Flag Tetra care guide. Compatibility here means water, temperament, tank zone and adult size all line up — the note on each card says why. Flag Tetra needs at least 10 gallons on its own; every companion adds to that.
Excellent matches
4 · Same water, complementary zones, no conflict.
Neon Tetra
Paracheirodon innesi
10 gal min · 1.5" adult · Peaceful
Similar size and peaceful temperament, excellent schooling companions
Cardinal Tetra
Paracheirodon axelrodi
15 gal min · 2" adult · Peaceful
Compatible size and peaceful nature, thrive in similar water conditions
Otocinclus
Otocinclus vittatus
10 gal min · 1.5" adult · Peaceful
Peaceful bottom dweller that helps control algae without competing for food
Harlequin Rasbora
Trigonostigma heteromorpha
10 gal min · 2" adult · Peaceful
Similar size and schooling behavior, compatible water parameters
Good matches
1 · Compatible with normal care — watch space and numbers.Also recommended alongside Flag Tetra
Species whose own guides list Flag Tetra as a tank mate.
Planning this tank?
Run the whole stock list through the calculator — it checks bioload and schooling numbers, not just pairings.