I am loving all the photos. Thank you for sharing.
Yes, I used Frontline. The spray above looks like it contains pyrethrins, which some mites can be resistant to. I tried Frontline Plus, just 'cause, not really expecting it to work. But it did. I used the full-strength Frontline Plus (which has the growth regulator [GR] plus a killer) and I have no mites now, after 1 treatment. But I had tried the pyrethrin powder and ivermectin on the mites multiple times and got no where.
The Frontline Plus I used was for dogs. All the dog concentrations are the same based upon weight - but the volume is what's different. I used 1 drop on the back of the neck, one under each wing, and 1-2 below vent. That's 5 drops per bird (applied on the skin). One ml of fluid is about 20 drops, give or take. So multiply the number of chickens you have by 5 to get the number of drops you need, then divide by 20 to find out the number of mls you need, then figure out what "size" dog you have.
I needed about 15 ml to treat my flock of about 60 birds. So I bought the large dog ones, which are 4 mls each. I ended up using 4 of them. I did waste a bit in the beginning before I figured out exactly how I was going to do it all.
Some people use the Frontline spray, but it's a much less potent concentration of fipronil and doesn't contain the GR S-methoprene. I think the addition of the GR is what made me not have to do more than 1 treatment so I'll be sticking with the Frontline Plus.
I was going to do a second treatment, but I had mono... but learned something good with it - one treatment works.
Just for full disclosure I did clean the entire coop and did some bombs with the GR in them, as well.