Can bettas live with crayfish?

Verdict
Yes, with care

Yes, with care. Bettas and crayfish can share a tank, but watch one thing. They only share 76–77°F. Keep the heater set there and steady.

BettaBetta76–82°F · pH 6.5–7.5 CrayfishCrayfish65–77°F · pH 6.5–8

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Both: 76–77°Betta 76–82°Crayfish 65–77°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Betta 6.5–7.5Crayfish 6.5–8
The green band is the pH both tolerate.

Size to scale

Betta · 2.5 inCrayfish · 5 in0"1"2"3"4"5"6"
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

BettaCrayfish
Temperature76–82 °F65–77 °F
pH6.5–7.56.5–8
Adult size2.5 in5.0 in
Minimum tank5 gal20 gal
TemperamentSemi-aggressiveAggressive
Swims atTopBottom
GroupOne per tankOne per tank
DietCarnivoreOmnivore

Better tank mates for bettas

All betta tank mates

Better tank mates for crayfish

All crayfish tank mates

Questions

Can bettas live with crayfish?

Yes, with care. Bettas and crayfish can share a tank, but watch one thing. They only share 76–77°F. Keep the heater set there and steady.

What temperature suits both bettas and crayfish?

76–77 °F. Bettas need 76–82 °F, crayfish need 65–77 °F.

What size tank do bettas and crayfish need together?

At least 20 gal, set by the crayfish. Add space for each extra fish.