Curled Leaves - Blue Dream Strain

Hello everyone!
I am growing cannabis indoor for the second time. This time I choose to grow 2 Blue Dream plants and 1 Hindu Kush using LED lighs (~150 watts).
They were doing well but during the last days I am noticing that one of my Blue Dream are presenting weird curled leaves:

The other Blue Dream and the Hindu Kush seems to be pretty good:

I am doing exactly the same thing for all of them, same soil, watering, fertilizing, light period and so on. So I think very strange that only one plant is presenting these symptoms.
Any though that might help me?
Thank you very much in advance!

Have you seen the sticky post about photos under HPS or LED?
Follow the guidelines and you'll get plenty of support.
Good luck

How much are you watering them?

@Mullumbimby , they are not under the LED light, they are on my bed
@Bsmoke78, that was the issue. Apparently they were starting to be underwatered, for some reason, one of them started to presetn symptoms first. Today (next day), all the plants are looking good and healthy!