I’ve got some week old chicks for the first time and am doing my research into what type of bedding works best for a coop. I have access to river sand but am also interested in trying out coffee grounds. Unfortunately bulk bags of grounds aren’t available in my area so I would just recycle the coffee I use at home. If I slowly added these grounds to a base of sand, would that work as a hybrid style bedding? Are there any rules against mixing bedding types?