We finished a small "winter run" for our chicken. The dirt level was low, so we added some mulch from a 2 year old mulch pile and some loose dirt (hard to find here in PA, we have mostly clay soil). I also found a bag of organic potting soil and "regular" potting soil that was just going to sit in the shed all winter, so I threw those in there. The "regular" potting soil has TONS of perlite in it. Now I'm not sure what to do. Will perlite harm our chickens? Do I need to scoop out as much as I can? Can I add some soil or sand on top of it? Is it ok the way it is? I was orginially going to plant grass but have since learned that it won't last anyways, so I don't believe i will. This run is about 8'x8'. They have a larger "temporary" run on the other side of the coop. This run is covered and ultra-secure and we are planning on using it in the winter and on days when we're gone all day. We have 4 hens and 1 rooster and a 8' x 12' indoor coop.