Our hens just began laying about a month ago. After the first week, some of our 18 hens were laying very soft shells that were almost like a skin, while others were laying perfectly good shells. We went out and got a 20 lb bag of oyster shell, about $8 I think, and offered it at free will in a food bowl next to their feeder. We have not seen any problems since. We use a layer feed combined with scratch grain and our birds free range from dawn to dusk (with plenty of tall grass, garden area or mowed pasture to pick from. We also provide them table scraps. (They LOVE cottage cheese, or any cheese for that matter.) My recommendation...you can use the oyster shell if you notice your eggs are breaking too easily or the shells or soft but it is not necessary. I'm with Buttercup Chillin...apparently my ground didn't offer enough calcium for them either.