One of the top choices to pair with crayfish is the brown pencilfish. This tiny fish often hovers near the top of the tank. Their appearance is quite unique, with a sleek, thin, and elongated body.

If you want a multi-species aquarium that includes crayfish, consider top-dwelling fish, like tetra, betta fish, and goldfish. They won’t interact with the crayfish on the tank’s bottom and ...