Most people do not realize the effects a poisonous fish can have on your aquatic habitat. One wrong purchase and your entire tank could be killed off. These are some things to consider about poisonous fish. The main distinction between poisonous fish are Venomous and Poisonous.
Venomous fish inject there poison whereas poisonous fish simply excrete or exude it.
Poisonous fish let their toxins into the water, eventually wiping our every living thing in the tank. To humans most of these fish are not fatal. They can produce a sting and some swelling at the most. However, they are fatal to the fish in your tank. If you have a live rock system, it will also be killed by these fish toxins.