I haven't noticed it for a long time. But when you guys started talking about it here, had to go look at my tank to see it. 
 
I kind of like it though. It only shows up on the sand bottom, and reminds me of snorkeling and seeing the wave shimmers on the sand. 
		
	
		
		
		
		
			
		
		
		
		
	
		
		
	
	
	 |