they'll stay hidden for quite some time.  you can always try movin' them to a different part of the tank to see if they perk up.  don't go move them every day, give them some time in a different location maybe and see what happens to them.  they may be unhappy with some of the neighboring corals right now, who knows. 
		
	
		
		
		
		
			
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				Darryl
			 
		
		
		
		
	
		
		
	
	
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