Thanks for the replies, the roots are looking fine, the nutes I am using are the 3 stage fox farm, big bud, tiger bloom etc, using the correct one for each stage plus the all round one for all stages, the leaves that are damaged are halfway up yeah but mostly near the top and the leaves under are all ok at the moment, also, it's just this one plant out of 4 that is having a problem, I've got 1 dark devil, 2 big Buddhas and this one struggling is northern lights, all auto flower but northern lights is the only 1 having this issue.