Remove the sandbed and discard it -preferably a week or two on advance and don't add a new sand bed until the tank is in the final position. 
 
Is it possible you could get another 90-gallon tank? The easiest way would be to set up a tank in the trailer for a couple weeks first, then transfer everything, then move it all back to the original tank after the new build is done.  Also, I'm not sure if a trailer is structurally sound enough for a 90-gallon tank. I don't think trailers have the same building code requirements as houses, but I'm not sure. 
		
	
		
		
		
		
			
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				~ Mindy 
 
SPS fanatic. 
			 
		
		
		
		
	
		
		
	
	
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