Diatomaceous earth is sold almost everywhere that sells pesticides or hardware. Larger quantities are sold for swimming pool filters. Heck, people even eat the stuff.
using it as a filter to make DI water was all i ever knew it from, made non conductive water for the EDM machines... i'll look for someMake sure you don’t eat the stuff they use for pool filters though. Some of the DE sold is ‘food grade’ and other DE isn’t. We use a lot of DE around pets and our chickens but we only use food grade stuff. I also use it to get rid of aphids on my peppers and tomatoes.