Rather than a skeleton, they have a body of exterior fused plates that form a box.Their unique method of swimming, called ostraciform swimming, causes them to look as if they are hovering.They have no pelvic skeleton, so they lack pelvic fins.They have the ability to release ostracitoxin, a poison that can kill all tank inhabitants. They are able to feed on benthic invertebrates by blowing jets of water into the sandy substrate. Their diet includes polychaete worms, but they will consume other small invertebrates in the sand as well. They should be fed a variety of foods, including fish, clams, squid, octopus, shrimp, etc. They also require an equal amount of plant foods, such as seaweed and spirulina. Occasional offerings of pre-frozen peas and corn are also acceptable. In captivity, they equate the water's surface with feeding and will blow water out of the tank when they want food. It is one of the more entertaining boxfish species, as it will spit water from the tank or flap its pectoral fins at the waters surface to get attention.