What I mean is that when chickens go to roost, that is where they stay through the whole night. They can't see well in the dark and won't be up feeding or pecking... as long as it isn't light.
Lower flock members tend to go up earlier or later to get their spot.
Crud always rolls down hill. You can always try a time out on the worst aggressor. My friend hobbled (tied the legs together) their bully for a few days, to sow her down and shorten her stride. Worked for that one to take them down a peg.
Peepers are a possible choice if it was bad enough.
I personally dislike DE... and consider it especially ineffective in humid environments.
Red skin means ya got something, IMHO. Choose what you wanna treat with and do it. I MIGHT consider Ivermectin pour on, since it WILL treat scaly leg might, worms, lice, and others. I believe withdrawal time for eggs is two weeks. The spray I mentioned has NO withdrawal time when used according to direction. The spray can also be used on the roost (or other wood) to treat for mites which only come out to feed at night and are otherwise not generally seen on the bird. Lice can often be detected by parting feathers and looking at the base under the vent area, for clumps that almost look like dirt clumps.
As aart said, roost time after dark is a GREAT time to catch birds. Never chase them again, keep it dark.
Treat everyone.
And if you want... see WHO you like and rehome a couple or few gals keeping the ones YOU like the best... whether to your friend or someone else. That will shake up the order a bit, but fewer birds in that space WILL be more peaceful. I ALWAYS appreciate the lull and so does the flock. It brings them together a little more and also friendlies them up to me. Gives each more of a chance to shine as an individual.
Visual barriers are good. I put up false walls, like even a wire fence open on both ends... so there is no corner to get stuck in, and they can run around it if needed. Or a plant. a chair laying on its' side. Whatever.
