I am going to be purchasing my live rock and I wanted to know the best way to suppor tmy rock so it doesn't fall over or collapse on to my fish later on. Do I glue the pieces together, or I am just sopposed to leave them in my tank loose. I also do not want glue them in place forever in case I ever want to change the layout or remove a piece for what ever reason. Also, is there a good way and a bad way to lay out the rock. Besides athe obvious you want it look good, and of course good water circulation around them, is there anything that I should knoqw besides this?????:bum: