I used to...can't find that good sand anymore so use just about 1/8" of straight PDZ.I believe @aart mixes sand and PDZ on her poop board? Not the floor of the coop, but on the boards.
Gonna be lazy and just link to the old 'poop boards' thread:
Original....
https://www.backyardchickens.com/th...s-poop-pictures.621363/page-178#post-18966048
Updated...
http://www.backyardchickens.com/t/6...raphic-gross-poop-pictures/1100#post_13179595
Leave just enough to clean under them.I think you are saying leave plenty of room between the poop board and the roost. How much room? I was thinking 6 inches. Would you leave more?
The higher they are, the more likely you'll have 'overshoots'.