Anyone know why the leaves are like this?

zu viel Wasser !

that's stress from any number of things. Heat, humidity, watering, toxicity

Maybe cold or too warm water when watering?

maybe, bad watering habits? For soilless (coco et al) 1) Fully saturate with 10% runoff out teh bottom. The runoff is essential to avoid buildup over time. Don't scoff at this due to personal incredulity as you will learn the hard way. 2) Wait for appropriate dryback and repeat (loss of weight is an excellent trigger, too) if this causes any droopiness, it is the fault of how the media was constituted. cooc needs ~33% perlite or similar for proper aeration/drainage characteristics. The volume you use is not choosen by you. You give as much as it takes to accomplish the task. If you wait for same dryback, it will require a similar volume each time for planning purposes, but you don't get to choose what it is. you learn in hindsight. Usually i'd say this is climate-related, but according to info given your VPD isn't whacky.

Stick her in a bigger pot maybe.

Looks like a root issue to me. either overwatered or lack of O2 in the rootzone.

P,K problem plus could be Ca,Mg Make ur tap water 300 ppm (with CalMag) Then add 250-300 ppm with veg fert In sum it,ll be 550-600 ppm then water em with 20% runoff Use this solution every watering, then,ll see