Tell me about candling eggs... will a household flashlight work? at how many days will I be able to see something? what will I see... if alive... and if not? should it be dark around me... ie. dark room or night time? how often would it be safe to do this and check on things? do I shine a light up from the bottom, down from the top or from the side? what good does this do and should I throw away any that appear dead? That's all I can think of for now. Thanks.