I have one goin right now. 12/12 from seed grow. Definitely the least happy in my tent. Really pale yellowing starting from the too and fading back to dark green after a few nodes. One of my tallest 12/12 from seed currently, about 2.5 feet tall and just finishing up it's stretch and showing pistils everywhere.
Hmmm, sounds like it could use a foliar then. I just bought the supernatural instant jungle foliar spray today for veg/ seeds/clones.... i like the idea of not having to mix up a one time use batch for such a small amount of plants... this Baby is spray n go, always ready