I thought I’d ask the experts...I’ve had chickens for 10 years, but I can’t determine what I’m looking at. I have 20 three month old chicks in a huge coop. I’m using a poop board with PDZ for the first time. I always have used a board, but not with PDZ. The last few days, I’m seeing little black fras looking stuff in it. I keep checking the birds, but I’m not seeing any mites or lice... now what?