One thing is make sure you have accurate light however you candle them. I prefer to look at day 7 then 14 then I check again at day 18 when I increase humidity. Make sure to keep the eggs upright, wide end up when candling. The lines are good, those are the veins feeding the embryo. Spots are bad it's usually bacteria, that said I have had eggs develop and hatch with a few spots but not small spots all over. I also have had eggs develop a little slower but some how day 21 seems to be like magic and they will pop. Super dark shadows that don't move aren't good either but you can hold it out until the end, in my experience they really don't explode unless the temp around them drops rapidly. I have great success hatching in cardboard egg crates with the eggs in an upright position. Wide end up of course. Oh one more thing consistency is key if it doesn't move it could be napping it may move on day 14 or 18...or if your like me you'll take a quick peek at it again later on, depending on how many eggs I am hatching at a time. Good luck it's a great experience.
