I have 9 pullets that are 14 weeks old. I have a red sex link (that I think is my earliest potential layer--I also have Americaunas, barred rock, australorp, brahma, wyandotte, buff orpington). I blocked off the nest boxes because they were trying to nest and hang out in there. When do I unblock them for these pullets and how do I keep them from pooping in there? Also, what are you using for nesting material in the boxes? Has anyone tried rice hulls for nesting boxes?