Heh!!!
The norm for Carpets once they get established and you have good lighting and current.
Be very careful in the tank when working with bare arms. As it gets healther and becomes well-established, the potency of its nematocysts will increase proportionately. If you keep it long enough, you will eventually find this out if you work bare armed around it in the tank (I think they have some type of animal magnetism...

)
Great for a specie tank, or a fish disposal, but not much else as they will revent any other
coral growth from establishing itself in a field of fire around the capitulum.
Good Luck...