Top leaves curling

[Rayvon]

Upper leaves curling upward, at tips noticed leaves on the other two branches starting to turn a light green from tip of leaves back toward stem

 

[Toker1]

Too hot, too much light, and bad watering practices.
More than likely one or more of these three issues happening. Leaning more towards heat and light... but hard to say with such limited information given.

 

[Rayvon]

1500watt led about 2 ft directing over crop. Room temp. 67 to 78 over 24hrs did have a 81 on warmer day until returning to correct. On older leaves had light too close and received some light burn. Have treated for magnesium and boron deficiencies. Adjusted watering habits , less water more often ( two , three times in 18 hrs)

 

[Toker1]

Sounds like a light burn issue if you had that happen prior. With LED’s sometimes it takes a few days to show the burn.