Phosphorus Def?

Have 3 hgk plants in my 4x4 all from the same mother plant. One plant inparticular is showing striping on leaves. I am week 3 in flower. My ppm was 500 and run off was 6.5. I just flushed it down to 5.9 ph. Ill post a picture of the spots. Have grown this plant 3 cycles now and has been a breeze. Also im using canna AB and Canna Boost. Ill post a picture below. Was just wondering what yall think. Thanks in advance.

What is your medium? What are you doing for Mg?

Im in coco/perlite 70-30. I gave one dose of Cal mag two weeks ago. Im using tap water at 90-110ppm. I usually havnt had to add calmag very often.

6.5 pH suggests you're feeding too high of a pH, which, if you think your meter is reading correctly, is allowing you to be mislead. Your run off should be closer to 5.8. I would dial in your pH and most likely the deficiencies, especially being you have experience with this strain, will disappear. Good luck

Thanks. Will do!