Please Help Me With Diagnosis

[SwitzerGrows]

I normally grow outside, this is just a cheap set up I have in an extra room in my house. Mylar blankets, a grow light, humidifier and fans. The plant seems very healthy over all. But idk what this leaf curling on the edge is. I'm having a hard time regulating the heat in the room. It's been really hot outside and the insulation isn't to good in that part of the house. I've been running about 60 percent humidity but at about 80 to 85 degrees, so the VPD is running higher then I'd like, average of 1.5kPa. It could also be wind burn because im trying to offset the high heat with more fans. If anyone can tell me what my problem is I would appreciate it. Idk if it's nute burn, light burn, wind burn or to dry because of the high VPD.

 

[Sativa1970]

Early sign of heat stress. Increase air flow and lower the temp. If you can't do that, lower the light intensity. As you know from growing outside, they can handle 85 deg. It is the balance of humidity, light intensity and fresh air flow that are wrong in an indoor grow for high temps..

 

[Phytoplankton]

@Sativa1970 nailed it, heat stress.

 

[SwitzerGrows]

Yea I turned my light down to 75 percent and turned the humidity up and it is already looking better.