My tank is set for 26 Celsius (usually 26.3 on digital thermometer).  My heaters vary by a couple degrees but I have yet to see it really move lower then 25.5.  I find the my fish and coral are happy at this temperature and the only time it fluctuates any more then previously described is water changes. 
		
	
		
		
		
		
			
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				300g Basement Reef - April 2018 
			 
		
		
		
		
	
		
		
	
	
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