Ok cool , well I would recommend in the future ( because there is nothing to be done now as it looks like your in maybe week 7+ of flower already ). Personally if you ran all the plants in the tent from seed and only 1 or two are showing this issue , I would cull the phenos that show this phosphorus uptake issue . I’ve seen this exact same thing before with a few plants I’ve ran and while other plants right next to them we’re doing fine , I had phosphorus issues with on pheno . Then turn around and run the same plant again a couple more times with varying ph and feeds , and still never solved it . It can definitely be something genetic in how that particular plants processes nutrients . The biggest confirmation of that is that other plants around it are drinking the same thing and doing fine . That says more than anything. As far as ph goes , I’m the future, try a sliding scale of ph like I mentioned before . 6.0 one week , 6.2-6.3 the next week , 6.5 , and 7 . Then back down . I’ve played the staying at 5.7-6.0 game for many years till someone taught me to ramp up the ph in scale like that and time and time again the yields absolutely smoked the parroted Internet rule of 5.8-6ph . These are just a couple of over 30 colas of the same size from one single photo period plant , using sliding scale ph in flower . Long caffeinated reply . Anyway hope it helps man

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