Light or Nute burn?

I brought home a clone from the dispensary yesterday, and threw 'er in my cab. This morning I woke up and checked on her and discovered she was burned in the midst of the night. Now, I assume I had her too close to my light, but I'm running a 400w hps in a vented cool tube, and the cool tube is warm, but I can indefinitely leave my hand on it, so I assume it isn't all that hot. On top of that, every forum I have looked into involving bleaches top level leaves, people always point the finger at nutrient burn. But I'm planted in mixture of 80/20 FFOF/Perlite, so I find nute burn hard to believe. So, really, I'm just sitting here blazed and confused over the subject. Any help would be wonderful. Suggestions? Since then, I have moved the plant down from about 3 inches away from the light to about 18 inches.

Looks like heat stress/burn to me, a 400watt should never be 3 inches away from your girls. Give em space to breath, looks really stressed out. Might be a while before she bounces back. If you don't know how close to have your light simply just do the hand trick, if you cant keep it under there for longer than 30 seconds then its too close.

I don't know the exact distance for a 400 should be, never used one. Do more research.

Well, as I said, the cool tube is never even too hot to touch, which is what has left me wondering.

http://www.growweedeasy.com/heat-light-stress

read and compare, its clearly heat stress. Keep your distance.

Word, thanks for the pointer, man.

np, but like i said earlier just give her time and she'll bounce back.

Mire said:

Well, as I said, the cool tube is never even too hot to touch, which is what has left me wondering.

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Most likely the plant was under weak T5s or CFLs before he got it. Takes a couple days to adapt to the stronger light. Still, 12 incher or further is a good practice, even with cool tubes. Mine burn if they get too close to my cool tubes.

Be patient. The plant will outgrow that little burn in no time.

Yep 8" to a foot would be good distance, you have to allow sufficient air flow in your canopy...they'll bounce right back as stated

Try 18 to 24 inches away bro

Heat stress... Nute burn will burn your tips as well.

very simple place the light from the tip of your finger to your elbow away from the plants, I use a 600 watt at tthat distance and have never had a problem, you should be just fine with a 400! happy days

heat stress... but it looks like you've fixed it already... since the top looks clean and green...

three types of burn you'll see...

Nute burn - affects the ends of the leaves (will move inwards, usually won't burn the ridges untill it's traveled at least 1-2cm)

Heat stress - usually affects either the center of the leaves (when a low wattage light is too close) or the ridges ( ridges of leaves will curl inwards and dry out first (riges also includes tips))

Wind Burn - aka windshock... fan blowing too heavy on the plant can cause the side faceing the plant to prematurely dry out (causing burn) usually easy to spot since it's A. next to a fan, B. on one side of a plant

Hey guys, is the leaf curl on my gurl from the cfls? P.s I have a par 38 flood (cfl type) in amongst them.....

BumP........

Scroga said:

Hey guys, is the leaf curl on my gurl from the cfls? P.s I have a par 38 flood (cfl type) iView attachment 2512855n amongst them.....

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only slightly on the edges... doesn't look too serious...

Canibitual said:

only slightly on the edges... doesn't look too serious...

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Good on ya for the reply mate!
I've got no fan in the veg tent,cfls don't really heat up, do you think it would stop the burn whilst keeping them close? Or is it a lumen thing? Cheers again Cani!