I have no idea of what kind of flow will go through the refugium.  I didn't think that a great amount was necessary.  I just wanted some to travel through there and most of it to go throught the baffles. 
 
The design I used was kind of a take off of one on Mels. 
		
	
		
		
		
		
			
		
		
		
		
	
		
		
	
	
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