Would love if you fine people could give your opinions on what could be going on here. These bronze patches seem to be mainly starting at buds and aren't brittle or dry. Could this be a boron deficiency?
Seeing as it’s the top cola that has the burn I’d think it’s probably from the light, you might want to raise it a few inches just to be safe. 20” is about as low as you’d want to go with 320w