1st Time Grow ~ Green Crack

Beginning of the week i noticed my light had slipped a couple inches closer to my plant then i would have liked... Once i noticed crisp leaf edges and obvious light stress I readjusted it. Lowers growth is turning yellow and dying off. RH is around 50% and at the end of this week will stay at about 40% Had signs of a nute burn last week and cut them half-strength, checked run-off PH, roughly 5.8 Having to adjust the lights just about every 2 days, shes really growing at a different pace Her structure has also changed, almost like stacking buds.