There is a handy little calculator online somewhere and I can't find it, your mag should be fine seeing as each turn or corner you put on a return reduces your flow substantially. You should be able to tell pretty quick if your overflow will handle it but I don't see it as being a problem. 
 
Doug 
		
	
		
		
		
		
		
	
		
			
			
			
			
			
			
			
			
			
				
			
			
		 
		
	
	
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