Can guppies live with koi?

Verdict

Yes, with care

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

Guppy72–82°F · pH 6.8–7.8

Koi59–77°F · pH 7–8.5

What to watch

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

What works

Both are fine at 72–77°F.
pH 7–7.8 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

	Guppy	Koi
Temperature	72–82 °F	59–77 °F
pH	6.8–7.8	7–8.5
Adult size	2.0 in	24.0 in
Minimum tank	10 gal	Pond
Temperament	Peaceful	Peaceful
Swims at	Top	All levels
Group	Groups of 3+	Groups of 3+
Diet	Omnivore	Omnivore

Better tank mates for guppies

All guppy tank mates

Better tank mates for koi