Can koi live with red tail sharks?

Verdict
Yes, with care

Yes, with care. Koi and red tail sharks can share a tank, but watch one thing. A grown koi may treat small red tail sharks as food, especially at night.

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–77°Koi 59–77°Red tail shark 72–79°
The green band is the temperature range both can live in.
456789Both: 7–7.5Koi 7–8.5Red tail shark 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Koi · 24 inRed tail shark · 5 in0"6"12"18"24"
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

KoiRed tail shark
Temperature59–77 °F72–79 °F
pH7–8.56.5–7.5
Adult size24.0 in5.0 in
Minimum tankPond55 gal
TemperamentPeacefulSemi-aggressive
Swims atAll levelsBottom
GroupGroups of 3+One per tank
DietOmnivoreOmnivore

Better tank mates for koi

All koi tank mates

Better tank mates for red tail sharks

All red tail shark tank mates

Questions

Can koi live with red tail sharks?

Yes, with care. Koi and red tail sharks can share a tank, but watch one thing. A grown koi may treat small red tail sharks as food, especially at night.

What temperature suits both koi and red tail sharks?

72–77 °F. Koi need 59–77 °F, red tail sharks need 72–79 °F.

What size tank do koi and red tail sharks need together?

A pond. Koi outgrow indoor tanks.