Northern Light auto by Linda Seeds *Organic guerilla grow*

It looks like the powdery mildew wont go anywhere with the spray I am using. Maybe cause it's been raining a lot lately and quite cold weather also. Had to remove some flowers and leafs cause they were infected. One of the plants seems to have some kind of deficiency as you can see from the picture. Is this potassium or is it a fungi, what do you guys think?