Have some yellow spots only on this baby, the 4 ot...

Hey Manapool, you have the start of a magnesium deficiency , i guess because of two reasons : first reason is the light is very strong for a small plant so the plant is getting stressed and needs more magnesium to grow. Second reason is the feed you're giving is good for the rooting process, but the problem is it raises the pH and the higher pH makes absorbing the magnesium and calcium almost impossible for the plant. I guess you're not pHing the input feed right? So my advice is to add cal mag and cut out the rhizotonic , make a spray with 2ml / L cal mag a spray it on 2 or 3 times a week. The problem should stop spreading within a 10 days or 2 weeks. Hope this helps ! 🚀