Can crayfish live with siamese algae eaters?

Verdict
Yes

Yes, crayfish and siamese algae eaters can live together. Both are fine at 75–77°F. Plan on at least 30 gal.

CrayfishCrayfish65–77°F · pH 6.5–8 Siamese algae eaterSiamese algae eater75–79°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–77°Crayfish 65–77°Siamese algae eater 75–79°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Crayfish 6.5–8Siamese algae eater 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Crayfish · 5 inSiamese algae eater · 6 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

CrayfishSiamese algae eater
Temperature65–77 °F75–79 °F
pH6.5–86.5–7.5
Adult size5.0 in6.0 in
Minimum tank20 gal30 gal
TemperamentAggressivePeaceful
Swims atBottomBottom
GroupOne per tankAlone or in pairs
DietOmnivoreHerbivore

Better tank mates for crayfish

All crayfish tank mates

Better tank mates for siamese algae eaters

All siamese algae eater tank mates

Questions

Can crayfish live with siamese algae eaters?

Yes, crayfish and siamese algae eaters can live together. Both are fine at 75–77°F. Plan on at least 30 gal.

What temperature suits both crayfish and siamese algae eaters?

75–77 °F. Crayfish need 65–77 °F, siamese algae eaters need 75–79 °F.

What size tank do crayfish and siamese algae eaters need together?

At least 30 gal, set by the siamese algae eater. Add space for each extra fish.