Anyone ever see whitish mucous hanging from the stem of clones when in either a bubbler or aero setup? Plants aren't suffering, but wondering what that is...
If it's a growth of some kind, then it's a fungus and not good. Keep a close eye on it, if it looks like a web of white, it may be powdery mildew. For unrooted cuttings, that will be fatal.
I just had some of the same stuff, but on my dwc roots. I can't be 100% but it's very likely that is was caused by my ph up/down. I guess you ph'd you're water, so that could be it.