Hey noticed this (pic below) on the stem of one of the girls today. I wasn't sure what it was but assumed the worst and killed her. Out of curiousity what was it I'm starting to think maybe I messed up.
Hmm. I'm not really sure what that is but it kinda looks like some sort of mold or fungus. It's only one clone so I wouldn't worry about it too much. Good luck and take care.
Looks like either a bit of scum, or a little algae growing there, but I'm a soil grower so not to sure of my diagnosis, I would ask POTUS, or one of the other Hydro guys here.
Growdude was right. That is the magic work of what a rooting hormone does. Totally normal. It makes the stem explode with all sorts of funky growth at or below the grow medium level.