We started using sand about 4 years ago, by accident. We had HORRIBLY wet, stinky runs that winter and I just happened to think about the big creek that runs through our property. We loaded up the Gator and rode down there, and sure enough, both sides of the creek were lined with the whitest, finest sand you could find. We took that Gator load and put it in the run, and that's where it all started. Now we have 6-8 inches in every coop and run and it works WONDERS under wire bottom brooders. Keep the flies away. Sand will be a GREAT investment if you plan on having chickens for a while.