I got 5 very healthy chicks but what about the eggs not doing anything? Can't really see anything candling. SOme are very dark eggs, Someone said to gently shake them and listen for peeps. When I did that some felt like something was loose inside. Some felt heavy and solid. Some real light. No peeping. I'm not real good at the float test. Any other ideas? I hope I have more hatch. Or is this about normal?