I have a seven young hens that are starting to lay. I am getting an egg thats shell is like leather, not hard shelled like the rest. THis egg is from a barred rock or a golden sex link. It has happened now four or five time. They are on layer pellet with oster shell mixed into the food and a small tray of shell on the side. I was wondering if any one else has had this promblem before, Or if any one knows what might be done to fix this? I would hate to cull such a young hen.