Our old adobe brick coop is infested with ticks, they live in every crack and crevice. It's a severe infestation. We had to pull out the old nest boxes and burn them because of these ticks. We soaked the chickens in a mix of castile soap and water for the mites, we found out that there is three kinds of ectoparasites on the poor hens, mites, lice, and ticks. We are cleaning the coop today. We just discovered the ticks in the nestboxes today, and found that frontline plus for dogs is good for the mites that live on the chickens bodies so we ordered it but it hasn't arrived yet. We have DE to lay down on the floor of their coop, but for the walls we are unsure what to do, we are thinking bleach, pesticide, or maybe latex or roof paint. But what we are sure of is that we can't let our chickens back into the coop until these pests are completely wiped out. We just can't have them, and we had to get rid of almost everything in the coop because of the infestation. Right now we're keeping the hens in a separate coop, it's like our quarantine coop, but it's way too small for eight chickens, in fact, we normally wouldn't put more than two or three in there. They have been in that coop since we soaked them yesterday evening. What would you guys suggest? What would you do if you had this problem? Please help. We really don't want to resort to pesticides.