Can crayfish live with lemon tetras?

Verdict
Yes

Yes. Crayfish and lemon tetras make a good pair. Both are fine at 72–77°F. Plan on at least 20 gal.

CrayfishCrayfish65–77°F · pH 6.5–8 Lemon tetraLemon tetra72–82°F · pH 5.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–77°Crayfish 65–77°Lemon tetra 72–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Crayfish 6.5–8Lemon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Crayfish · 5 inLemon tetra · 2 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

CrayfishLemon tetra
Temperature65–77 °F72–82 °F
pH6.5–85.5–7.5
Adult size5.0 in2.0 in
Minimum tank20 gal15 gal
TemperamentAggressivePeaceful
Swims atBottomMiddle
GroupOne per tankGroups of 6+
DietOmnivoreOmnivore

Better tank mates for crayfish

All crayfish tank mates

Better tank mates for lemon tetras

All lemon tetra tank mates

Questions

Can crayfish live with lemon tetras?

Yes. Crayfish and lemon tetras make a good pair. Both are fine at 72–77°F. Plan on at least 20 gal.

What temperature suits both crayfish and lemon tetras?

72–77 °F. Crayfish need 65–77 °F, lemon tetras need 72–82 °F.

What size tank do crayfish and lemon tetras need together?

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