Clawing/Curling leaf

Hi all,

This plant is in a DWC system, ph ranging from 5.6 to 6.2.
Room temp light on is 27-28c with 45-50%RH.

she's 5 week into bloom and not all but I notice the small leaf tend to curl/claw downward.
Res been cleaned, I'm very clueless what could cause this.

Thank you

She's nute sensitive. You'll have to take it easy on this one.

I have one strain that does the same think when it gets too much nutrients,

Thank you all, her uptake was all fine until week 4-5 of flowering, she's getting picky.