I am constantly putting coral frags in my fairly new tank.  the next day i find some in the sand bed and sometimes I cannot find them at all.  Later I find a floating plug it was glued on.  I have a fairly large urchin that does a great job on keeping up on things, however, I wonder if he is knocking things around at night?
Any thoughts would be appreciated.
								Any thoughts would be appreciated.
 
				