Can koi live with rosy barbs?

Verdict

Yes, with care

Yes, with care. Koi and rosy barbs can share a tank, but watch one thing. At 24 inches a koi can swallow a small rosy barb. Fast, alert fish usually stay out of reach.

Koi59–77°F · pH 7–8.5

Rosy barb64–77°F · pH 6–7.5

What to watch

Watch outAt 24 inches a koi can swallow a small rosy barb. Fast, alert fish usually stay out of reach.

What works

Both are fine at 64–77°F.
pH 7–7.5 suits both.

Water side by side

The green band is the temperature range both can live in.

The green band is the pH both tolerate.

Size to scale

Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

	Koi	Rosy barb
Temperature	59–77 °F	64–77 °F
pH	7–8.5	6–7.5
Adult size	24.0 in	4.0 in
Minimum tank	Pond	30 gal
Temperament	Peaceful	Semi-aggressive
Swims at	All levels	Middle
Group	Groups of 3+	Groups of 6+
Diet	Omnivore	Omnivore

Better tank mates for koi

All koi tank mates

Better tank mates for rosy barbs