Ostraciidae- Boxfish

Boxfish belong to the Ostraciidae family. They are often referred to as Trunkfish or Cowfish. Most of these fish are members of the genera Ostracion, Lactoria, or Tetrasomus. Boxfish reach an average size of three inches in an aquarium, while in the wild, they can grow to over 19 inches. Boxfish are closely related to both Puffers and Filefish. In most cases male Boxfish are larger and more colourful than their female counterpart.

Boxfish are easily recognized by their distinctive square or boxlike shapes. Their sides are actually bony plates covered by a thin skin. This becomes important if there are so-called cleaner fish in your tank, as the Cowfish’s delicate skin may not tolerate this behaviour. Two pairs of bony horns distinguish the Cowfish – one on the head and one just above the caudal fin. The horn-like protrusions from the head and above the caudal fin deter predators. Some Boxfish can release a toxin called ostracitoxin, which is used to ward off predators. It is important to note that if this toxin is released into the aquarium, all the tank inhabitants can be killed, although this does not occur often. Boxfish are found throughout the world, and are most commonly associated with coral reefs. They can also be found near rocky areas, sand flats or grass beds. Most of these fish are found in harems of one male and several females. The breeding of these fish in an aquarium is extremely difficult.

It is imperative to maintain Boxfish with peaceful tank mates as they are often easy targets for more aggressive fish. If over one Boxfish is to be kept in the aquarium, it is advisable to introduce similar sized fish to the aquarium simultaneously.