Betta Fish vs Rainbowfish

Side-by-side care comparison to help you choose.

Betta FishRainbowfish
DifficultyBeginnerBeginner
Adult size2.5-3 inches3-4 inches
Lifespan3-5 years5-8 years
Min tank size5 gallons30 gallons
Water temp76-82°F74-82F
pH6.5-7.56.5-8.0
TemperamentSemi-aggressive; males aggressive to each other, can be kept with docile tank matespeaceful
Tank matesSmall peaceful fish like neon tetras, corydoras, and snailsPeaceful community fish like tetras, rasboras, and corydoras.
DietCarnivorous; feed high-quality betta pellets or flakes once or twice daily, supplemented with frozen or live foods like bloodworms or brine shrimp.Omnivorous; feed high-quality flake or pellet daily supplemented with frozen or live foods 2-3 times per week.