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		+1 on the internal I have 2 one in each corner 6 x 6 each. By 16 inches high never gonna clog and a fifty gallon sump for a 100 gallon tank with a backup retun pump all wired to my apex my gf is much happier no more floods 
		
	
		
		
		
		
			
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				200 gal system.
			 
		
		
		
		
	
		
		
	
	
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