it's purple kush, it was cut last tuesday and placed in rockwool. i've been hardening it off every couple days until it droops and then popping it back in the dome. rockwool is the perfect amount of saturated, just barely wet to the touch.
with a semi firm pull i can't get it out of the rockwool so i assume it's probably begun rooting. i've had clones yellow one of the big fan leaves on the bottom but i've never seen this happen from the top before.
the only thing i can think of is the beginning of a nitrogen deficiency but i'm kind of hesitant to feed this thing while it isn't even showing roots on the outside yet.
ideas?