Set out for a planned voyage to find this stuff recently, thinking it would be a bitch to find. Went to 3 pool/spa stores and 2 carried the same brand Dia-sumthing. $8 for 10 lbs. Now if I could figure out how to use it correctly. The guy corrected my pronounciation when "diatamaceous earth" was requested. So, some do know what it is. Its really fine grain, floats in the air.