We do already have a QT tank, although when a fish of that size, ~9" comes around a 20g QT isn't sufficient, or humane. 
 
I have never once heard to avoid large Naso tangs, and I myself did work in the industry for a short amount of time. Where did you hear this? How common is this knowledge, has anyone else heard of this? 
		
	
		
		
		
		
			
		
		
		
		
	
		
		
	
	
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