Boxfish/Cowfish reef safe?

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Are boxfish and or cowfish (same thing?) reef safe? If so, everything I've read said they are dangerous and if stressed enough, could wipe out my whole reef. Would any of you risk it? Or is that all just an old wise tale?
P.S. I'm asking because my girlfriend saw one yesterday at our lfs and she wants him. lol She has BAAAAAAAAD luck with the fish she picks out for MY reef. First she wanted a Koran Angel, then she wanted a Copperband Butterfly...and I'm not taking a chance with the butterfly.


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They are reef safe from what I know. But if they are stressed enough they will release a toxin that could wipe out the reef like you have heard. Also they are not good swimmers and cannot swim in high currents. They can grow up to 10-18" depending on the species.
IME Boxfish and Cowfish will make a nice snack out of corals and any other inverts they can catch.
IMO treat them like you would puffers.
boxfish and cowfish are not the same thing. the cowfish have horn like things coming out of their forhead and boxfish are just square like. also they are not reef safe, not to mention they get huge. and on the worst part alls it takes is for them to get scared once for them to release their toxin or they get stressed out by something to relase the toxin and boom you have to start all over again


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My opinion on cowfish is that the reef is more detrimental to the cowfish than the fish is to the reef. They are very clumsy swimmers and have a difficult time feeding in the high flow conditions of reefs, not to mention that they also have to deal with the competition of other fish to get to food. I can't generalize on the cowfish's tendencies towards eating corals, but can say that the one I owned never touched any of the corals it was kept with.
Unfortunately, the tank I kept that fish in had too much flow and too much competition to deal with (a French Angel and a Naso Tang), and I found it dead and stuck to a powerhead intake one morning. The fish lived through some traumatic times before it's death, and it never released any toxins. The lesson I learned in keeping that fish, is it's best kept in a system specifically designed for it (along the lines of a seahorse system).
i had a cowfish for about 6 months til it got caught on the overflow box and died. it didnt really bother my corals, but it ate every fanworm in the tank. cool little buggers, but i wouldnt get one again i dont think unless i had a nano tank with very little current or overflow boxes.
The big misconception about cowfish is that they release toxins whenever stressed. I have never met a lfs or individual that has had a cowfish release toxins. Believe me, I have asked a lot of lfs. I think I happens in near death, being eaten, situtations or after death when the body has been decomposing for multiple days. This is just my two cents because I always hear people freaking out about that, but you never hear of it happening to someone first hand.
Now, of course, a ton of people will probably respond to this saying it happened to them.
That always happens.
Originally Posted by korgull
i wouldnt get one again i dont think unless i had a nano tank with very little current or overflow boxes.
A cowfish tops out generally in captivity at about 12"..definately not suitable for a nano tank.
I have one in my semi aggressive w/ a few corals and he is doing great.The not reef safe part comes from their desire to eat small inverts.This tank also houses a bluespot puffer,a tiger jawfish,freidmani psuedochromis,and a sandhopper blenny.The inverts in this tank were chosen carefully,so that they would'nt be harassed by any of the were the few corals.