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			#21  
			
			
			
			
			
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|   It is usually a problem with deeper sand bed and usually the sand on that spot become sort of black or dark.  The way to prevent this is by having sand sifting snail, like a conch or something limilar.  It will go inside the sand and aerate it. How deep is your sand? It if is only an inch or 2, I doubt that's what hapened. |