Help needed nearly cowfish?

I am considering getting a cow fish for my saltwater tank, there are corals and a couple other fish in the reservoir. I heard that they can release a poison in the water which will snuff out every thing else in the tank, what i stipulation to know, is, why do they do that and under what circumstances? is it very common/ or do they very once in a while do it?

Thanks!
Yes, they can do that. If it happens, it will kill everything within the tank, including the cowfish.
They do it as a defensive measure, when they find scared. In the ocean, it slows down predators while the fish has time to acquire away. In the aquarium, though, there's no place to get away to, so the fish (and everything else within the tank) is stuck in its poison.

How often does it happen? It's greatly unpredictable. It might happen the first day you have the fish, or anytime next, or never.
It is called ostracitoxin. Cow fish can do this if they are stressed severly or picked on by other fish. Understand this also kill the cow fish.

What are you planning on keeping him with? It is very uncommon since those who hold these fish understand this.

Know what you can and cannot keep with your cowfish and keep hold of the stress levels down. Remember as well, when they die or become sick they will release toxins into the water as all right.

This really is rare.
Answers:    if they are getting picked on, being netted into/out of a container, or otherwise stressed they will release..

ostracitoxin (the stuff given off by boxfish) can wipe out a tank surrounded by hours

it's not common for them to do it (only because people housing them are SUPER careful) but if self careless it's a very real opportunity.

boxfish are also not reef safe
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