Bro the tent is a 4x4 and they almost hit the roof LOL light couldn't go any higher and anyone can veg for weeks and make a huge plant... it's how your buds flower that makes all the difference,, mine are more solid than most hydros or coco grown and the living soil makes a lot more terpenes...
Imo as far as living soil goes, (which is far superior to any hydros) bigger is better, stepping up to a living soil bed with at least 350litres is key!
I can tell you right now no one put anything on the weed IV had the exact same issues and I produce everything on my own. What I think it is is some form of mildew that grows on the trichomes and no one has documented it as it's very hard even impossible to see while the plant is growing unless...