@NamasteDave, thank you for the detailed explanation!
Some good food for thought;)
As for the minor rusting you have on some leaves, I wouldn't be worry about that in this stage of flowering, it's natural to see some (not a lot of course) spotting and yellowing on the leaves is completely normal at the final stage of the plant and it won't slow down bud development to my opinion..
But yeah the Cal mag situation it coco during the final stage that's interesting..
Let me know what you found out ππ±
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