get Food grade diatomaceous Earth sprinkle freely on the birds, or put in a low box for them to bathe in and sprinkle in the coop and run will get rid of the mites super fast,
While I am new to this site I am not new to chickens having had them much of my life. I love the eggs and the endless variety of colors and breeds available. I have Easter Eggers, Olive Eggers, Rhode Island red Silkie crosses, Silkies, Australorps, Guinea Hens, Buff Orpingtons, and Lavender...
for wing sexing can only be done up to three days old I believe. The males wing feathers will all be even, females will have one long one short and keep alternating that way, long, short, long, short etc. Hope this helps.