In every hatching I had/have this year, almost every chicks ends up with closed eyes. It starts around day 4 for about a week. I must clean them up so they can see and eat/drink. No crust, just closed. When I clean them up, they open them only for an hour or so. When their eyes are shut, they are chirping little babies. Otherwise, when eyes are cleaned and open, they are fine. I clean up my coop evey day. I tried putting antibiotics in their eyes but it doesn’t do any good. Any idea what to do with it? Trying antibiotics in their food? Which one? Penicillin? Something else to try?