Sorry about the mites, but glad that you found something that can be treated. Permethrin 10 concentrate is also very good and a small bottle can be mixed with water in a spray bottle or garden sprayer to use on the chickens and also in coops, nests, and on roosts. It makes many gallons of spray, and the instructions are on the inside label. The dust is preferred especially during cool weather. Mites require treating every 7 days at least twice to get the live ones and then the newly hatched ones.