Both are fine, externals can be setup to not fail. But, my internal takes up less room, and makes things a bit cleaner looking. I guess I don't like things hanging on the edge of the tank. But given the choice, with an empty tank, I would still recommend an internal. The box portion can be customized for different needs and doesn't have to take up a lot of room. 
		
	
		
		
		
		
			
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				Brad
			 
		
		
		
		
	
		
		
	
	
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