i try to keep the lights at least 18inches away from the plants. but closer to 24 inches
I thought that it might be the light as well and checked the height of the lights about 5 days ago and each there after. Moved some plants put the tallest under one light, thought that I could be getting hotspots. I am about to post a pic of 2 plants, same garden, same watering schedule, same nutes. Hardly any burn at all one, the other one is another story. There are a few have no burn whatsoever. I promise to be more regimented on my next grow, with out a doubt and will also be doing some changes on the up keep.
10" fan will be here friday... will be looking to vent the lights with 4" fan. A whole nuther can of worms...
I had about 16 gallons ready... flushed the plants that needed it most or had the most to loose from nute burn. Will be preping more water for tomorrow... but I thought you only needed 24 hours of lead time to use water?

aww hell! had i thought of I would be as smart as you!
Use tap water to flush then finish'em off with prepped water. Duly noted for next issue.

The reason i let mine sit for 2 days is that i only visit my rooms every 2 days.

ya dude cut back on the nuts...how close do u have ur lights?

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Posted that info already... 18 inches at least... 24 inches last time I checked.
Here's the pic of the two plants... on the same watering schedule.


You can't blow up the pic but the plant on the right has a more even discoloration, and no nute burn on the tips... still liooks like to me that it may have a zinc problem. Veins are still green, but in between some of the leaves have turned color.
Plant on the left, has the burn.
One question I do have is... Do the lights accelerate Nutrient Burn? Some leaves when shadowed by another leaf only burn on the exposed part of the leaf... the part covered remains green. Kind of like water on concrete when exposed to sun evaporates and that in the shadows stays longer.

i still think it looks like the lights are burning them....a 1000 watt light is powerfull i only use 430 and when i burned my tips they looked the same...get a fan blowing over the tops when the lights are on if you don't already have one........you know who you should ask.....Widowmaker...send him a private message whenever i have had a problem he has always had the right answer....good luck

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I have the fan but maybe its not enough...

check this page out might help you

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