shiverled up leaves

[bonghitter]

Hey guys, i have just started to notice this on the big fan leaves. Any idea as to what's wrong, thanks!

setup-
400W HPS, promix soil, foxfarm nutrients, lights are 18inch from canopy, temps have been 70-80F, humidity 30-40% (a little on the dry side)

One thing I worry about is pH since I have only been using tap water and haven't been adding any PH down (did a great grow without adjusting PH so I've been lazy with this one in that respect). Oh yeah, I'm growing feminized "ICE" from femaleseeds.

[iStaaHi]

over watering maybe? my plants looked like this and i slowed down on the over watering and it went away,

[HiProGlow]

How old are they? Do you have a fan for circulation? It does look almost like a burn, perhaps nute burn but it looks more like a burn caused by the heat of a light but you say you have them 18" away from you light. Is the circulation good in your room good? Peace.

[dutch.lover]

yeah i would check your heat. cannabis plants don't take heat fluxuations too well, so that could be your culprit. also pH could definitely be an issue.

[bonghitter]

Thanks for the replys. I will plan on checking the pH and see if that helps. I don't think it's a temp issue as the hottest it gets is like 80. Circulation is good, I've got 2 blower-type fans running when lights are on. The plants are 2 months old, second week into flowering. Being that they are femenized I hope I get mostly ladies and no hermies. Peace.