thx for the answers guys, and yes that all in one day.. just a few leaves, the older ones that were exposed to direct sunlight, the younger leaves still ok.
i still wonder if the sun light and the hotness r just speedin up the overfert symptoms, wht u guys think?
btw, today i made a 15min flush at the morning and im avoidin direct sunlight.

Thx, any help is welcome.