I found an abstract online from a veterinary med. journal saying that DE and sulphur in dust baths was 100% effective for getting ride of NFM. But I can only read the abstract since I don't subscribe ($400 a year!!) so I don't know how much. I would only do this temporarily as I know it can be harmful - tho at least it is not pesticide. We brought mites into the coop unwittingly in a bale of hay - my husband got them on him, too, from carrying it, but that's another story. Anyway, we have bathed the girls in tea tree shampoo, dipped them in vinegar water and sprayed them with poultry protector and put DE in the nesting boxes and burned the hay --! so we are well on our way but want to do this one last thing. Thanks for any specific into you can offer.