My temps and humidity have been steady... I've been maintaining 50-60% humidity and 68-75 degrees temp... though humidity dipped to about 40 last night, which I corrected when I noticed.
It does seem to be effecting new growth and not the old growth, yeah. At least that's the yellow tips phenomenon. Though the one that is purpling, the purpling is mostly showing up on new growth as well. (Stems are already purple, but it's actually crawling into the leaves themselves...)
Over thanksgiving I had to leave the plants for a few days so I cracked the windows, and then it actually got pretty cold... but I came home on a cold day in the evening (20-30 degrees outside) and it was still over 50 in the room. Is it possible I cold shocked one plant that was a little more susceptible to purpling while the rest did not?
Several of the others have purpling in the stems, but I didn't think anything of it til I saw it crawl into the baby leaves on this one plant, since purpling in the stems seems pretty common in healthy plants... though, now that I think about it, when I pulled the plants out into normal-colored white light today, I did think some of them were remarkably dark green, almost to the point that I could say it looked a little odd.
I will be able to determine whether or not the drooping is a factor when I see how much they perk back up from the watering.
And yeah, I've got some pics taken, I just haven't gotten 'em off my camera yet, I'll get on that momentarily.