my snp has some mods but i would like to regulate my temp better and also would like to use less charcoal. right now i have sheet metal in the bottom with holes all the way across the bottom. I have seen were others have used sand and water i dont need the water but i want to use the sand , but not sure how .........i thought about putting it in a alumnum pan covered with foil so i can keep it clean and reuse it but what type of sand? i have seen the play sand at HomeDepot and Lowes , do i need to "wash" the sand before i use it ???? is there a sand i should not use "like from the river " .........just a thought?!