I've just set 20 eggs 3 days ago in the bator and I'm really starting to think all but one may not be viable. I candled when I set them in the first day then again today, which is technically day 4. Day 1 I had one that was clearly 3 days ahead of the rest and now there's a blurry red ring all the way around it but I'm still seeing some good veins. I've read several times around here to wait till 7-10 days before tossing them in hopes of getting some clarity. I have 1 other blood ring, but that one too still had some really good looking veins and it doesn't look like the pictures I'm seeing around here. Most of the rest are clear as far as I can tell but the shells are really thick so I'm waiting on those too. So my question is, can I keep adding eggs over this next 4-6 days or so to the incubator? And, does candling do any damage, am I okay to candle every 3-4 days till I'm sure I've culled out the duds?