Another POssible Source for DE (Turface Substitute)
Everyone talks about the Napa floor-dry (#8822) and the need to sift it. I've bought 3 bags over the winter / spring and all of them were too small, even after sifting. The size is much closer to 1/16 with a few in the 1/8th range. I lost a lot as powder/sand size during sifting. Too much work!
I have a friend that works in a shop (not a gardener at all) and he was cleaning up and oil spill with a DE product from CarQuest. He sorta looked at me funny when I bent over, grabbed a handful, and examined it, ha. It is 7.99/bag so more $ than napa, but it was very very uniform size 1/8 to 3/16 with almost no dust and a low percent in the 1/6th range. I'm soak testing it now. 8 hours and still crunchy :)
Anyways just thought I'd mention. Yours may vary. Check it out if your looking though. I'll get a pic comparing them soon.