I heard that too, but I heard it very late in the game. I'm at the Eastern base of the Sierra Mountains, my house is at 5,500 feet. This is the high desert, so it is dry here. The thing I didn't understand is that the humidity in the incubator should not care what the humidity is outside of the incubator (yes, they ARE correlated and incubator humidity is affected by room humidity), what I mean is 30% RH at 97˚F here should be exactly the same environmentally as 30% RH at 97˚F at sea level. At least I think that's true. I understand that we are discussing altitude not just the RH but I'm not sure I understand how they relate to each other.
As far as the eggs go, well I have some bad/sad news. At the end of day 50 at about midnight I still heard a heartbeat in the one egg. Not much wiggling but a heartbeat for sure. I had already removed some of the tape (the air cell end had no tape) but there was still tape on the rest of the egg. There was no sign of an internal pip (I don't really know what I'm checking for other than a chick who whistles back). The next morning at about 6:30am there was no heartbeat. I couldn't hear anything at all and I got zero wiggles.
My heart sank.
I took the rest of the tape off and immediately bored a small "safety hole", I knew it was probably dead but figured I had nothing to lose by trying.
And that's where I am today, I think today is day 53 and I'm pretty certain they are both dead. I was going to open up the egg yesterday but didn't. I will probably open them both tonight.
I had lots of tape on them and was running at 50-60% RH at 97-97.5˚F for the last third of incubation time. Even then my daily losses were more than they should be.
Before I started I had read one seemingly reputable write-up that said to "start them dry" and several other accounts saying the same thing (retrospectively I think the other accounts were merely citing the initial write up). So I did just that - started them dry - they lost nearly four times the desired daily weight loss in the first day! That single day was detrimental and I tried to catch up every day after that with no luck. That article should have said "in my climate at an average humidity of X and an altitude of Y it works best to start them dry and only add water if needed". I am not trying to blame that bit of mis-information on the loss of my chicks but if I take that single data point out then the final weight loss is right around 17% (still too much, but possibly survivable) but with that first day the final weight loss was just over 19%. I clearly had lots of time (49 days or so) to fix the problem but struggled hard to keep loss below 2.5g daily!
I regret not adding tape sooner and I regret not starting them at at least 30% humidity. And I regret being so afraid to cross that mythical 40% RH boundary. If I ever try again (I hope to) I will be sure to aggressively handle weight loss early on and I will be less afraid of high humidity. I might know more after the autopsy.
Sorry for the long post.
I hope yours do better than mine!
-Logan
Oh wow, I'm so so sorry to hear all of this! I'm hoping for wiggles soon, but that sounds really hard to deal with, knowing that there was an alive chick but possibly died. I'm very sorry, but I'm so glad you tried. Will you be trying for more eggs? Maybe chicks? If you didn't crack them open yet, maybe wait a little longer unless you're absolutely sure. If you did, however, did they pass? At least it's a learning experience, maybe see if they were dehydrated, or maybe even bloated. i hope the best for you! Maybe try again! It's just nearly unbearable not knowing if there are alive chicks or not for 4 weeks..