Hikari Medaka tank mates
Oryzias latipes
5 rated pairings from the Hikari Medaka care guide. Compatibility here means water, temperament, tank zone and adult size all line up — the note on each card says why. Hikari Medaka needs at least 10 gallons on its own; every companion adds to that.
Excellent matches
3 · Same water, complementary zones, no conflict.Ricefish
Oryzias woworae
10 gal min · 1.5" adult · Peaceful
Closely related species with identical care requirements and peaceful temperament
Least Killifish
Heterandria formosa
5 gal min · 1.5" adult · Peaceful
Similar size, temperament, and water requirements; both prefer cooler temperatures
Ramshorn Snail
Planorbarius corneus
5 gal min · 0.75" adult · Peaceful
Peaceful scavengers that help maintain tank cleanliness without competing for food
Good matches
2 · Compatible with normal care — watch space and numbers.
Red Cherry Shrimp
Neocaridina davidi
5 gal min · 1.2" adult · Peaceful
Peaceful invertebrates that share similar water conditions; provide hiding spots for shrimp
Otocinclus
Otocinclus vittatus
10 gal min · 1.5" adult · Peaceful
Small, peaceful algae-eaters that occupy different tank zones and prefer similar temperatures
Planning this tank?
Run the whole stock list through the calculator — it checks bioload and schooling numbers, not just pairings.