Cowfish 

Cowfish are found in the unique family Ostraciidae. In this family you will also discover the boxfish, a close relative of the cowfish. The family Ostraciidae is located in the order Tetraodontiformidae. Along with Cowfish and Boxfish, you will find Triggerfish, Filefish, Puffer fish, Burr fish and Porcupine fish in this order.

Cowfish have many different names, trunkfish, turret fish, and boxfish. These names are all used interchangeably. When adding cowfish to an aquarium it is best to add them first because of there ability to release a poisonous toxin knows as Ostracitoxin.  Cowfish have no pelvic fins because they lack a pelvic skeleton. In place of a cowfishes pelvic fins you may find a small bump. Like other Tetraodonts, cowfish have the ability to expel water from there mouths. This ability is used to dislodge prey or other food items from a small enclosed area. Cowfish will also use this tactic when the owner comes to feed the cowfish, usually spraying the caretaker in the face, a personality trait that these fish could develop.

·        Cowfish along with other Tetraodonts have personalities traits such as greeting the owner with a fanned tail and blowing into the substrate

·        These highly advanced fish along with other Tetraodonts split from other fish over 40 million years ago. There are four suborders of Tetraodontiformes

·        Ostraciids have the ability to release a poisonous toxin know as Ostracitoxin.

·        Fish from Indo-Pacific regions are commonly referred to as Boxfish, while fish located in Atlantic-Caribbean waters are sometimes referred to as Trunkfish

·        Cowfish bodies are made of rigid, hard plates fused together to form their carapace like body

·        Cowfish have a special form of swimming that only they are able to do also know as ostraciform swimming

·        These intriguing fish have powerful jaws, reflecting there natural diet of  crustaceans, corals, and sessile invertebrates

·        Numerous species of cowfish are found in all tropical seas

In The Aquarium

Cowfish are generally easy to keep aquarium inhabitants. They are peaceful and interesting residents of your home aquaria. Cowfish are unique in their possession of horns. The keeping of cowfish in aquaria often results in the shortening of these horns because of the repetitive encounter with the glass sides of the aquarium. Keeping the same species of cowfish and other ostraciids is not recommended in aquariums for the reason that they may become extremely aggressive, exercising no tolerance for the other inhabitant. It may be possible to keep a male/female pair in large aquaria. They may however be kept with other species of Ostraciids. It is best to have only one species of cowfish per tank. Cowfish can also be kept with docile inhabitants. They should not be kept with aggressive fish for the reasons that the poor cowfish will end up getting no food, and that a cowfish is more likely to release its poisonous ostracitoxin. Cowfish should be kept in nothing less than a 75 gallon, a 125 gallon tank being recommended. It is possible to keep small species of cowfish such as the thornback cowfish (reaching only 6 inches in size) in a tank as small 55 gallons. A wet-dry filter is recommended because of the high waste output cowfish produce. A protein skimmer is also recommended but with excellent filtration is possible to get by without one.

Ostracitoxin

            Ostracitoxin is a poison that the ostraciids have developed as a mean of defense. Therefore in the home aquaria there is risk that the aquarium residents including the cowfish itself are susceptible to being poisoned. If not taken care of right away it can result in unfortunate fatalities. Ostracitoxin is only released when disturbed or frightened.   Therefore by keeping a cowfish with docile fish you are also helping prevent the fish release its toxin.

Biology

Cowfish are unique in the possession of a carapace resembling armor, made of fused polygon shaped plates. In their carapace like armor there is a gap for the mouth, an opening for the gills, and gaps for the caudal peduncle and fins. Cowfish are slow swimmers; therefore they are propelled by movement or their large dorsal, anal, and pectoral fins. They have a single large dorsal fin located towards the posterior. Cowfish also lack pelvic fins and a small bump can be observed on some species. Extremely powerful jaws and thick, textured lips are also present on the cowfish, helping to grasp algae and uprooting invertebrates from their spot. Common to popular belief cowfish do not have the ability to puff up like the puffer fish.

                                                Diet

            A cowfish will accept almost anything from plankton to algae. A cowfish is best fed three times a day unless there is a substantial amount of algae or live rock for the cowfish to browse upon during the day. Then it is only necessary to feed the cowfish twice a day. You should feed your cowfish a varied diet of shrimp, clam or mussel on the half shell, squid, octopus and worms. A substantial amount of vegetable food should be fed too. Defrosted peas, broccoli, and seaweed are general idea of the kind of vegetable matter to feed your fish. Frozen foods such as mysis shrimp will work too. It is important to feed brine shrimp to your cowfish as a treat because by including it as a main part of the cowfish’s diet you are just making it fat. Brine shrimp also have a low nutritional value.

Tank Maintenance

Regular water changes and vacuuming of the substrate are a must in cowfish tanks. Cowfish like puffer fish are to sensitive water conditions. Ammonia and nitrite levels should be as close to zero as possible. When nitrate levels reach 40 ppm the aquarist will know that a water change is needed. When the pH level begins declining this is also a sign that a water change must be done. The sensible aquarist will want to keep his pH at 8.0 or higher.

                                                Conclusion

Over all cowfish are great aquarium inhabitants and will quickly become an interesting member of the aquarium. With their great personality traits such as blowing into the substrate and greeting the owner with a fanned tail they are simply irresistible. With the right conditions a cowfish can become a long living enjoyment.