Further, I do think you can "recycle" used rock to a degree by cooking, and maybe get a year or three more out of it. Buying new rock is tough, as most LFS that I know of don't have new rock, they have used rock that they buy from people shutting down. So unless you're ordering a fresh box, you may get worse rock than you took out. 
		
	
		
		
		
		
			
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				Brad
			 
		
		
		
		
	
		
		
	
	
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