I had a similar problem and it turned out to be humidity. The leaves would curl up and the stem would look a little white or pale (almost like it was shedding).
I just took out a fan and then put bowls of water around the plants so the light would evaporate it. Seems to be working.
You should keep your humidity around 40-60 percent.
I would also move your light a lot closer.
Good luck with your grow!
Last edited by Raelum; Dec-17-2008 at 22:06.
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