Elector PSP and Oxine are two nontoxic bet very effective items I keep on hand for any mite or lice issues, and for disinfecting (may be the wrong word). They are both expensive but I have a flock currently of 23 and even though I have completely enclosed and covered runs for them, lice and mites show up every once in awhile. These two items also last forever. Two examples: 6 or 7 years ago I was given 3 Silkies and I was fairly ignorant about diseases and pests with chickens because I had never had any issues in 30 years. Kind of amazing but the truth. Those three brought in a virulent bird flu that spread to every chicken across three separate coop/runs. We had to put down most of my Silies, Ameraucana's, and Speckled Sussex. Then I cleaned and used Oxine probably 4 times in 6 months over winter. I finally got rid of that nasty stuff thanks to Oxine. Elector P is frankly a miracle. I have a hand sprayer with pump and mix that and clean out coops, spray them down and evening when they are roosting we spritz each bird. I had lice and mites hit them, I also sprayed the runs down and the outside of the coops including any surface inside then put new shavings in. It killed all the mites and lice. Love the stuff. So easy and very effective.