i just posted on your other thread. i think this is normal. however, the yellowing sound like it could be a root prob, considering that you are using cool whites. try a root builder nute at very low strength and wait and watch.

i will say this though. my blueberrys turned yellow on the edges once they were five nodes high. yellow stayed forever, but plants grew like hell, and new foliage was nice and perdy green.

let us know whats up!

love, brooke