nearest white sand beach or golf courseseriously, pool stores will sell it, probably landscape suppliers (as long as it's the right type) consider zeobrite which is half the weight for the same volume and much better filtering capability. it cost me about 80 bucks for 2 -50 lb bags (equivalent to 200 lb of sand for example) which is 'dirt cheap" (pun intended) when you think it will last you for years and years with proper cleaning maintenance.
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