I spelled out diatomaceous earth in the subject line because the search engine won't look for two letter words plus I think some people may not know what DE is. Anyway... my question. I have a 4' x 4' foot coop with a vinyl floor and about 3 inches of wood shavings in the bottom. How much DE should I use to keep it dry, odorless, and flyless? It's very expensive here and I certainly don't want to be wasting it. $23 for 2.2 lbs, although I bought 3 jugs of it at last year's price of $17. Can't believe they raised the price that much in one year. 33% Wow!