Help! Diagnose please! PICS

day 65 of super critical haze grow. dont know exactly whats going on. leaves are turning black. Also it seems as if i still have a nitrogen def. due to the leaves at the bottom.(or is it?) should I throw in some of the MG all purpose(24-8-16) with the bloom to fix the problem?


Light:
8 clfs (23-26w)
1 6500k
2 5000k
5 2700k

12/12 cycle

Soil:
MG potting mix

Nutes:
Veg: MG all purpose
Flwr: KGro bloom

thanks!

Looks like something got dripped on them and is burning the leaf but i dont see a N def the plant is just getting older but if you think you still have give her a little and make her green. The only thing that can cause black patches is K def and that all purpose food has some so if that is the case it will clear it up in no time.