New Grower What could cause this type of curling?

[Rastacan]

Hello everyone,
I just started my first grow with 2 different types of autos and today I've run into a little problem. Does anyone have any idea why that leave could have been curled? Everything was perfectly fine till I put my light little bit downer and half an hour later I saw this! I just don't understand if it is caused by heat or whatever it is, why didn't effect the rest of the plant(s).

 

[Need4Weed]

It sounds like it's light related to me. What kind of light are you using and how far away is it???

 

[Rastacan]

Im using 600w HPS and it is about 40cm away. Air conditioning is perfectly fine and it is between 24-27c all the time.

 

[namvet25]

I wouldn't worry to much about the curled leaf but if it happens to more leaves I wou;d move your light up some.

 

[Rastacan]

Ok, thanks =) Now it is sleep time for the babies and i'll check them (as everyday) first thing tomorrow. I think I am so excited since it is my first grow xD Thank you again

 

[pop22]

leaves curl up on the edges from heat stress

 

[Rastacan]

Yeah, I raised the lamb a bit and it worked, they seem fine now. Thanks for helping =)

 

[rockthestalk]

I have the same problem, so thank you also for the help