Need help yellow spots pics included

Hey rollitupers lol. I have some yellow spots appearing on one of six plants in the same reservoir. They are growing in an aero system under a 600 watt hps with adequate ventilation. Temps rarely get above 80. They are all autos but this is the only one that is berry bomb. The are being fed A.N. ph perfect trio with b-52, piranha, and voodoo juice as additives and A.N. cal-mag. They are almost to flower. Ive tried top include a much info as i can think of at the moment. If there is anything else you need to know just ask and any help is really appreciated.

Anybody?

Please guys i need some help

I see heat stress along some edges but I can't really tell what you got going on regarding the white spots, do you have any other pictures ?

Ill take some more and post them. I posted another thread bc this want getting many replies and someone said it may be to much calcium which makes bc the last time i added cal mag i remember thinking it may have been too much. What did you think?

Yeah heat stress is the only thing I see! If temps never touch 80 then maybe your lights to close around 20 inches is good! Those spots I wouldn't worry about bc it's so early if you start trying to fix shit that ain't broken you could just cause more problems! But if your growing by the bottle just make sure you follow the instructions and make sure you not leaving anything out!

Looks like it could be powdery mildew.