our big maroon didnt stop pushing sand around after he started to host in our tank. but he did slow down alot on it. but now he loves to beat up corals around his area, so that is something to watch out for.
i would say a RBTA is the best one to start with if you are going to get one once you have good enough lighting. i wouldnt put more then 1 in at first, and never put more then 1 type in the same tank at a time, the clown can transfer the stinging cells from one to another and it can hurt them. if your water is in really good shape and you have good enough lights it will split at some point and you will have 2, so i would only start with 1. here are pics of both of our maroons hosting. first one is our bigger one in our 150, 2nd is of our baby gold strip maroon in our 30 nano.