I've had a couple spots where different sps have encrusted and started to grow where I didn't want them to.  I found a couple of good fixes... 1 - if the rock can be taken out, torch the unwanted frag with a lighter, 2 - if not, just cover the spot where it is growing with a little marine epoxy... and a frag that you do want there... or just the epoxy if you prefer.  This will smother it, and problem solved.   
 
For the longest time, I would scrub them with a tooth brush thinking that the stress would kill them... somehow they would survive, which blows my mind. 
 
That said... people like free SPS frags!! 
		
	
		
		
		
		
			
		
		
		
		
	
		
		
	
	
	 |