I have read a bad review on one brand of the permethrin 10 but the 13.3 is mixed for cattle, sheep, goats, dogs, flies in stalls, stock yards.... Abf good reviews. I was shock at the way it dropped my fly problem. No flies for weeks after one application. You mix this stuff 1 1/2 oz per gallon of water it will kill every bug in the coop. Just spray everything. Under roost boards, under poop boards... Every stick of wood. Clean the best box, spray the nest box, fill the nest box and spray the new bedding as it may be how its coming in. mix 1/2 oz per gallon and spray under birds wing and her back as she runs away. Spray coop and birds once a week for two weeks. Then birds ever other week. After spraying the coop, nest box and bedding once a week for eight weeks and birds five times you still have mites. Burn it down and move. I spray my coop once a month (when I add pine shavings and clean the nest boxes) and birds once every other month. No bugs, no flies. The only fly problem I have had was the out side run, around the compost pile and grass around the coop. I spray that every other month now.