Death keeps coming. Help requiered.

Well i have 4 PPP and White Ice flowering. 5th week.
Soil: Soil Mix (sawdust+soil+worm soil)
Watering: Every 3-4 days (when totally dry)
No extra nutes added @ this point.

They were all flowering first under CFL (260W) and then i got the HPS 250W bulb. I placed them under the HPS and they looked happy. NOW 2 weeks later (pic 1) one of the plants suddenly DRIES out. I think this is because the ballaster heat that was next to her....

I move the ballaster 30cm away to prevent further burning.

3 days later.... SAME PROBLEM. One of them looks like shes taking the same stress that the first one had. Leaves become VERY dry, and looks just like a burning plant IMO.

Does this look like heat stress? I still have 2 (or 3 depends if this one lives) that i can save and im pretty sad for this right now...

http://img24.imageshack.us/img24/8201/dsc02720v.jpg (Image 1)
http://img26.imageshack.us/img26/1745/dsc02724x.jpg

Does this look like heat stress? (i believe it is) And is there a way to help the plant get over it?

Check temps and check your ph. i think kyou said earlier you don't have a tester...well find one fast and check it.

I'd say it's a lil more than heat stress at this point. Could be over fert or a def. I'm not sure on your soils NPK and trace mineral values, you should find that out.

You probably should have given them more nutes, they probably burned through what was in the soil before flowering and giving them some flowering nutes would have helped.

Fill out the form, don't half ass it like you did above or we can't help you, only give you 20 different things it could be.

There are several things that could be causing your problems, and heat from the ballast could be a part of it, but there's mostly likely other causes that need to be rooted out. For instance, sawdust makes soil acidic, and you need to have a way to test the pH of your water and soil. Even if it's just pH test kits for aquariums, which are available practically anywhere, it's important to know (and regulate) your pH.

Along with that, fill out this form as best as you possibly can. It's hard to guess what all might be causing the problem when we don't know hardly any details about the grow.