Although the cute little yellow longhorned cowfish that is offered for sale in your local fish store are so adorable that it literally begs to be taken home to your tank, this is not a fish to be bought on impulse (actually, no fish should be bought without knowing about it’s habits and mature size). The drawbacks to this fish are that it gets large – 16” or so -- it needs to eat a lot, and until it is used to a tank it is a very skittish, and can do itself harm by running into or becoming wedged in the tank and decorations. Finally, the longhorned cowfish can release a poison if stressed or when it dies that will completely wipe out a tank.
The longhorned cowfish will eat anything, both meaty foods such as shrimps, squid, clams and enriched brine shrimp or krill, and also the frozen prepared foods designed for herbivores. It is not, however, a very aggressive eater, although it needs to be fed two or three times a day. It cannot compete with tankmates that are pushy and aggressive eaters, and is best kept either in a species tank by itself or with other slow moving and non-aggressive fish.
As long as the drawbacks above are understood and you are prepared to give this fish the conditions and feeding it requires, the longhorned cowfish makes an interesting pet, as it becomes tame and interested in the world outside its tank.