Manganese deficiency?

Some of the plants have been discolored and younger leaves dying before they get bigger than a penny. Theyve been getting fed and some are fine so wondering why the discoloration and growth stunt

What is your environment like? Temps, Rh, etc.

Need more info on grow. Water schedule...feed. medium. ..lights using...more info the better.

Water 3 days a week, spray with kangen water twice a week. Using pyganic for spider mites which are pretty much killed off. Stays arounf 70 degrees in tents. Pretty humid 65%. Feed every other week with hydrofarm nutes. None of nutes have manganese in them. Fox farm soil medium. Using 5000k fluorescent lights. Defintely not enough light for how many plants there are but waiting to get greenhouse up so they have to do for now. Both tents are around 500 watts.