Ideally you want something bigger than 29g for a sump. Power outages may very well over flow the sump, depending on your drain config and sump water level. And 2600 GPH thru a 29 might be a bit much.  
For my 90, my sump is 110g, but you could probably get away using a 40g. 
		
	
		
		
		
		
			
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				Brad
			 
		
		
		
		
	
		
		
	
	
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