I have a red star, that started laying about 4 weeks ago. First eggs were normal, after 2 weeks she started laying eggs without shell, but membrane around. I took her of the kitchen scrabs and gave her just the pellets. After 3 more eggs without shell, she started laying normal again. Now, 2 weeks later, it is starting all over again. For 2 days, eggs with membrane, but no shell. Is there any reason to be concerned that there is something wrong? She looks absolutely fine. Yesterdays, the no shell egg had two egg yolks. Can she maybe not produce calcium fast enough? Should I feed all my chickens oyster shells or anything in addition? Can I feed kitchen scrabs (just vegetables and fruit) or should I not give them any at all?