If it is leg mites I have a suggestion and it will be a pain to do.
get a large pot with a lid...might want to purchase one at good will..
buy cheap cooking oil enough to fill the pot up to 5 inches and cover it..take it out to the coop and leave it till night time roosting.
Every night,remove the lid on the oil, lift a bird up off the roost and dip the legs in the pot..count to 10
do every bird, even ones not noticable.
Eventually the birds oily legs will also kill the mites living in the coop and discouragee them from reattaching.
You need to do this for a solid week.
Keep the pot in the coop
In a month you need to do it again
Than re evaluate
get a large pot with a lid...might want to purchase one at good will..
buy cheap cooking oil enough to fill the pot up to 5 inches and cover it..take it out to the coop and leave it till night time roosting.
Every night,remove the lid on the oil, lift a bird up off the roost and dip the legs in the pot..count to 10
do every bird, even ones not noticable.
Eventually the birds oily legs will also kill the mites living in the coop and discouragee them from reattaching.
You need to do this for a solid week.
Keep the pot in the coop
In a month you need to do it again
Than re evaluate