Need whole plant pictureI use cal-mag by general hydroponics. 1mL per liter. Grown in coco with perlite. pH of runoff is 5.8. pH of water with nutrients is 6.1/6.2. RH and Temps are good. Using Canna Coco A and B nutrients. The black spots seem to not be on the newest growth. It's still a pretty young plant.
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Not calcium deficiencies, but zinc. Any macro nutrients in the line u using?