I just put down sand mixed with some pea gravel in the new run area. Now before I let the girls in there should I mix some of the food grade de into the sand. And if so about how much. The total run is 6x12, but I only put sand/pea gravel in a 6x6 area which is the part with the roof. Should the grass/dirt also be dusted with DE or just the sand area? I am learning as the girls are growing- 8 weeks old this week.