Hopefully I haven't left it too late to fix, added nitrogen fertiliser (liquid) 1ml/1ltr with their nutrient mix, waiting a few days to see if they get back that lovely green colour again, probably should of left the damaged leaves on until I see healthy new growth but I cut a few of the worst looking ones at the bottom.
@Budbuddy84, thanks mate your's will be as good . Just give them what they need and rest will come i switches to flowering week 6 because ran out of hight real-estate 🤣