I love this forum. It has helped me immensely.
I was doing research on D.E. because I want to add just a little to my sand filter. Well, I don't need or want a 25lb bag. I thought maybe the insecticide kind would work. No, the chemistry and process is different. The D.E. for the pool is heat treated to make it more crystallized or calcined. Lo and behold, at Napa Auto Parts, they have a product called "Floor Dry part #8822" that is exact chemical composition of D.E. Filter Product. It is only a little over $8 for 24 qts. Will update weight when I get back with it.