We finished building our new coop yesterday. I only have silkies and am wondering what the best coop flooring would be? My research is pointing towards sand because I want something that is low maintenance and clean and not smelly. Our run gets quite muddy. I was thinking of laying pebbles in there (they free range all day so won't be on the pebbles to much) but it will be quite expensive. How would sand go in the run?