Purple Punch Autoflower(Fully organic)

Pheew, 2 different results going on, very interesting to see very different results. The sickly yellow plant(centre) looks sick i am assuming many factors are involved. I have listed out the potential error which caused the plant to yellow much faster compare to the other healthy purple punch. Here is my ADHD mind self figuring out😄. 1) Light stretch during seedling-2weeks. Energy to form strong branches, i guessed this because this plant released trichomes before the other. Way too fast. 2) PH pen- Time to change to a new one, PH fluctuations could also be another reason. 3) Top dressed bat guano too much- they are highly soluble i read, so the plant yellowed and burnt off crispy. The other purple punch is looking solid with so many white pistils coming out. This plant did not yellow as fast as the other( centre plant). I will be targetting to harvest in 5 weeks time maybe more depending on the trichomes. Cant wait to see this fully organic grow.