i have a gs maroon that i've had about a year. it is about 2-2.5 inches. i can not add coral without the maroon knocking it off rocks or moving it. the maroon seems to move it where he wants it and then leaves it alone! if i move the coral back he moves it again.there is a few shrooms & leathers that were in the tank before him and he does not bother them. i do not have an anem. if i add one will he leave the corals alone?