bigdog

I honestly don't think that it makes a difference when you remove them from the germinating mix. I've removed them as soon as they pop up, and they do just fine. I've never once left one in to grow four leaves first.

Allen, sorry to see your problems! I would separate the one that isn't showing any problems from the others. It could be a soil-borne pathogen causing rot. If you have a fungicide, mix up a little of it in a spray bottle and lightly spray the plants with it. Water the ones you have potted up with it also at your next watering. Was your germinating mix sterile? That will make a huge difference. Also, it looks like you've potted them up into a mix with fertilizer in it. That may be causing the tip burn. They are still a bit young to start fertilizing. Good luck with them!!