That could be dried blood on comb or dry pox.
Bullying can be caused by crowding and/or diet.
Coop looks of decent size, but how many birds do you have?
Pics of inside, please?
Run looks a bit tight....and 'boring', need some 'stuff' in there for diversion and for lower status birds to get away from higher status birds.
Sleeping in the nests is not a good habit and could indicate other problems.
How old are birds?
Oh, and....Welcome to BYC!
@NewChixFarm36
Where in this world are you located?
Climate, and time of year, is almost always a factor.
Please add your general geographical location to your profile.
It's easy to do, (laptop version shown), then it's always there!
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