I have no clue about this deficiency. Tried cal mag, dried it out and flushed it with water 6.4 ph. Looks like zinc? I had picked most of the big fans with the disease and they seem to be coming back. It’s not central to the bottom. Growing indoors first time with mars 600 watt full spectrum. Happy frog soil. Fox farms trio 6.5 ph. Granddaddy purp 4 weeks into flower. Buds seem small. Not very pugnant or sticky. Can anyone add some insight please and thank you