I have sand in my coop and a dirt floor in my run and I have no smells. My ladies keep the sand and dirty scratched up enough that they cover up their mess very well. BUT we are on 34 arces in South TX so the coop is Very well ventilated. Generally speaking I shovel and shift the top layer of sand once a week (or less) to get rid of any chucky stuff, but other than that..nothing. After reading the threads on this site about sand, I chose that route vs putting in shavings or hay in the coop and haven't regretted it yet. I do have some hay in the nesting boxes.
