Curled top leaves

Ok so i was happy nothing wrong happened until now in this grow and i woke up to this. Yesterday was perfect, and from three plants she is the biggest and strongest one. Maybe the lights are hanged too low? I just bought some new lights and i’m planing to put them higher tomorrow, as i have to cut the closet)). So i’m really worried…just one week since i switched to 12/12

You could be experiencing over transpiration, heat stress, or light burn. They curl up to preserve over transpiration. (i.e.) They may be transpiring too fast due to too low humidity along with high heat. I highly recommend following a VPD chart to achieve optimal growth. Here's a handy link to follow.
https://vpdchart.com/#F,56,80.6,79.7,0

DoubleAtotheRON said:

You could be experiencing over transpiration, heat stress, or light burn. They curl up to preserve over transpiration. (i.e.) They may be transpiring too fast due to too low humidity along with high heat. I highly recommend following a VPD chart to achieve optimal growth. Here's a handy link to follow.
https://vpdchart.com/#F,56,80.6,79.7,0

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Thank you so much!!

SO at the flip, you should be at 79 degrees, and 57% humidity. Leaf surface temps should be around within 1 degree under your air temps. You will need a decent IR meter to see what your LST's are.

This should be your sweet spot, but temps, CO2 feed, and other things can affect this.. But if you can be within 1.2- 1.6 kPa, you should be fine. You can move the target to suit your environment, but stay in the 1.2 - 1.6 range on kPa during flower.

Highest I've ever gone was about 86 degrees, but your RH has to be higher. Typically, you want a 20 variant. Like 80/60RH, or 85/ 65RH... beyond that, and I think you will cook out your terps.

If it's only the leaves near the foil wall I'd say it's a hot spot area for light bouncing off the foil. If it's all over the place then just too strong a light for them. Flat white is best or that not so shiny foil.

I use a temp gun to check leaf temps and adjust the light up or down as needed. Just switched from a 400mh to a 600 and toasted a few myself.

Ok so yesterday i put one hour the new lights, i saw the leaves like that and put the old lights on, in 5 hours they are back to normalso i really need to put them much higher right?)

AntoMaria7 said:

Ok so yesterday i put one hour the new lights, i saw the leaves like that and put the old lights on, in 5 hours they are back to normalso i really need to put them much higher right?)

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Both LED’s or CMH?

AntoMaria7 said:

Ok so yesterday i put one hour the new lights, i saw the leaves like that and put the old lights on, in 5 hours they are back to normalso i really need to put them much higher right?)

Click to expand...

yes, higher, and get some PAR readings.

AntoMaria7 said:

Ok so yesterday i put one hour the new lights, i saw the leaves like that and put the old lights on, in 5 hours they are back to normalso i really need to put them much higher right?)

Click to expand...

Sounds like that's the solution to me. What are you using for light?