This is my 2nd time hatching chicks with an incubator the first hatch I had 20 hatch and still have 20 healthy chickens now I have had only 19 hatch out of 31 eggs and my chicks keep dying. I have already lost 7. They seemed to be fine and now everytime I go to the brooder there is another dead baby. What have I done wrong and is there anything I can do to stop them from dying? Please help!!!