need fast help

The problem I'm having is that ever since the temps down here have been more spring like instead of winter the leaves that are directly under the light are starting to get a little burnt; but all the other surrounding buds and leaves seem to be fine still.

A little about my setup: I'm growing 2 ak48 in dwc rubbermaid using the scrog method in the 4th wk of flower, growing in a 4'lx3'wx4'h cab (and I already have the light raised about as high as it can go) with a 600w hps in a cool tube being cooled by a modified stanley blower.

I suppose the question that I have is; should i bend the buds that are being burnt (even though the stretch has stopped) or should I upgrade to a more powerful fan, or maybe add a second fan like a duct fan or something (one for the light and one for cooling the cab)??? Any help or advice would be much appreciated. I'll post pics a little later once the light comes back on.

Kinda hard to tell from the pics but the ones towards the middle are like a bright faded green, and the ones away from the middle are more a dark green color

With that cool tube I could get it 6 inches from plants if the room is A/C and 2 or 3 good fans blowing right across the topps of your plants. Get a few fans like small oscilating ones to blow back and forth.

Without fans your cool tube is getting tooo hot that's why the light green burn on closet ones. A light with no cooltube could be raised up almost a foot higher.

OH and awsome buds there man.

Thanks for the advice; there is actually a fan that sits on the floor blowing up onto the plants from under the canopy, but you just can see it in the pics. I will defiantly go out and see if I can find a couple more to blow across the tops. Thanks again for your help