We have four new layers - two, the Rhode Island Red and Wyandott are laying perfect eggs. The Buff Orpington and Barred Rock are laying soft-shelled eggs. I've read several of the threads about the topic and am going to try adding calcium to their diet for a bit - the two soft-shell layers are much bigger than the others and I'm wondering if they just need a little boost here at the beginning of their laying career. Can I drop a few Tums and a vitamin D capsule into their water? I made them a mash of yogurt and feed to peck at today. How long do I add calcium and will it harm the two that are laying regular-shelled eggs? Thank you for this website - it's been a useful tool and true gift to us as we try this new foray into backyard chickens!