Big plants, small pots, and running a coco grow with a non-coco nutrient. Are you supplementing with any calcium source? If not, start now.
I've got no experience with that foliar product you are using. The upper parts of your plants look really good but my instinct says that won't last. You can't really rely on foliar feeding, and trying to do it right thoruhg flower is asking for mold problems.
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