Hi everyone! We're getting close to the point of needing to put some bedding in our coop/run. The coop is an old metal barn with a dirt floor. I'd like to use sand for bedding, but have read that it needs to be silica free. The lowest silica content sand here that I can find is what is called 'creek bed sand', and is a bit coarser than say, playground/sandbox sand. I was told it should be fairly low in silica, but they can't guarantee that it's silica free. Will this be okay to use as a bedding, as far as being safe for my chickens? Also, how deep should I plan the bedding to be? I figured 6", but don't know if that's too much/not enough.