First time posting because I'm totally confused. Have 4 2&1/2 yo barred rocks and 4 3&1/2mo buff orps. The barred rocks haven't laid a thing in almost 3 weeks! They've spent plenty of time in the boxes but no eggs. I've looked in every nook for a hidden nest but no eggs! Read in another post that scratch corn could be binding them up. How? What can I do to jump start them again?