There Looking good. But you need to increase your Cal-Mag dose.. The ones that have purple stems which magnesium deficiency can cause purple stems like that. I don't know if you can fix it this late in Flower but id at least try...I dose 2ml per gallon which is about 1/2 of the recommended dose. But i do it in every feed if i start to see the purple fade. then i'll double it till its gone. Then Back down again..
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