So I went to the feed store to get some crushed oyster shell since my female duck is getting close to laying eggs. It's recommended to start offering it 2 weeks prior. 2 weeks is a good one, since nobody knows for sure when. She is 15 weeks old so we are getting there, and she has been playing mom. She has been building nests, putting rocks into them, and sitting on them. I've put up a nesting box with one ceramic training egg in it and she sleeps on it. Its really cute when she covers the fake egg each morning. Well back to my original post. Feed store had oyster shell for $7. Not bad, but what do you do with 50 pounds of it? I have 8 girls and wonder how much they would eat in one year. I was "crushed" and did not buy it. Went to the other store and they had a 5 pound bag for 5 dollars. Lousy deal, but at least I don't have to store 50 pounds of it. How much do you guys use per year?