Balistapus undulatus is a hardy member of a saltwater aquarium. It
however has a reputation as one of the meanest fish in the aquarium
trade. Sometimes young individuals will accept tank-mates but an owner
should expect this fish to kill most fish and invertebrates that share
its aquarium. Serious consideration should therefore be made for
keeping this fish alone. The minimum tank size to keep a small fish
alone is 190 L. It is a slow growing fish, but as it gets older it
will likely need a larger aquarium.