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[hornet]

if you wish to use something natural looking you could get some red sand or yellow sand just make sure its not the colored stuff. You can also use white sand, i have used playsand but its too fine and it clumps. I'm using the fine sand from my local landscaping place which doesnt clump but doesnt look as good as the desert sands. If your not fussed on looks go for newspaper, alot cheaper.