My run started out as just the native soil. I used a rake with hardware cloth attached to rake it, scoop into a bucket and take to the compost pile. After a while the soil became mucky and had a sour odor. So we tried sand several inches thick. Still the same raking, scooping, hauling to the compost pile. A once a week raking was not nearly enough for me to consider it sanitary. Their feet would get poopy and often dirty eggs were the results. We started adding leaves, pine straw, twigs and a lot of it. Sometimes store bought wheat straw. These things adds carbon. When you add carbon to nitrogen (poop) there is absolutely no odor and no raking. I can now go in and get compost any time I need it. I love the deep litter method so much less daily work in the run.