try to get a sump with a dedicated skimmer chamber so that the water level doesn't change on the skimmer, or have an auto-top off unit.  if the water level changes constantly (from evaporation) then the skimmer doesn't work properly. 
		
	
		
		
		
		
			
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				Everything I put in my tank is fully dependant on me.
			 
		
		
		
		
	
		
		
	
	
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