Parasite treatments

What are we all using to keep those pesky fowl mites away this time of year?

I generally make sure they have access to a dust bath with sand/ashes/DE. I also try to make sure the nesting box material gets changed regularly. And of course, keeping the coop clean.

I make use of diatomaceous earth and wood ash.

I will do my best to hit perches/cracks/crevices with DE inside the coop as well as adding it to dust bathing areas like Matt.

I was recently talking with my grandfather about chicken maintenance and he mentioned the usage of sulfur dust for treatment of mites. I'm unsure of any further information on it so please don't take that as an endorsement. It just might be another avenue of thought for treatment.

I have pigeons and I am pretty sure they get the same mites: little little skinny black 3mm lines that wiggle up under the wings especially.
I do everything mentioned already, plus I check youngsters regularly and anyone looking sedentary, and give them a blood temperature water bath dunking in a sink or bucket.
It is crucial to keep the head above water at all times --
Pigeons don't have a coughing reflex.
I give it about five minutes and that drowns the little suckers!
The adults will bathe themselves and couples preen each other, but the young ones vary in their ability to self groom.
Unless it is really hot out, I let them dry off inside a plastic cage beside a heater indoors  otherwise in the sun until they look dry..
If one is lousy, which can happen with young ones on occasion, perhaps 3% max, I will quarantine them, keeping the bedding clean every day and dunking every 2-3 days until they are clear, with healthy poop.