@Dabber , the others looking good is a big clue, I think, hehe. Maybe she has a genetic propensity for something as yet undiagnosed. I've seen plants like this, seem troubled and a little weak, then they recover and do well. I think sometimes a particular plant reacts negatively to feed. Or, my fav theory, for some reason plant not full absorbing nutes. I've seen this, and then it's gone. Hope yours is self correcting too.