I will be hatching eggs with my class next week. This will be my third year doing it and was hoping to improve my hatch rates. I have two questions about lock down. I saw that some people are using egg cartons to keep the eggs from rolling around too much and to help with the mess. Are you using the top part of the egg carton and does it matter if it is from a 12 or 18 one? Secondly, if I can't open the lid at all during lock down, how do I add water? Thanks for all of your help!