Our duck hut and the surrounding pen area are getting SO mucky and stinky. I put pine shavings in the hut, but haven't figured out what to put on the ground in the outdoor run area. They free range threw out the day, but when we leave or aren't around we lock them in the outdoor run. it's become very muddy from the little pool and all the duck poop. It's also starting to smell pretty bad! I tried hosing the ground down, but now that the grass is gone it just makes it worse. What can I use on the ground? I tried dried grass, but that doesn't work very well either. Any ideas? What do you guys use to keep the stink down?