Dial back the nitrogen levels and the clawing should go away in a few days. It looks like you will be flowering soon, and alot of the time these autos really start to demand alot of calcium and magnesium. It's hard to tell from a distance especially under a Hps but it looks like some leaves are showing some signs of calcium deficiency.
Pythium is a nightmare, keep a close eye on it. I successfully conquered the dreaded root rot with the help of beneficial bacteria and fungus. I now use microbes throughout my grow, and it is tremendous for the plants. Google Heisenberg Tea and see if its something that interests you.
Good luck on your journey my friend :stylez rasta smoke: