Merry christmas and happy holidays everyone, It is snowing here and I need to put something in the chicken run for them to dust bathe. Their run is not big 32``x 100`` for 4 chickens. It is dirt covered with a thick layer of dry leaves being shred by them slowly. I have a charcoal barbecue. I read wood aches are ok but what about charcoal aches?? What else can be added without buying DE, play sand etc. I have a few bags of sanded grout is that harmful??