Nutrients or lights?

It’s seems like you are already in the process of correcting this as a previous issue. It definitely look like it had a potassium deficiency and probably calcium as well. I’d keep going with the bloom nutes for sure, just be careful to not to do hard that you wind up with too much as that’s not good for the plant either. The leaves are not going to just repair previous damage. What you wanna do is keep an eye and make sure it’s not progressing, and that other problems aren’t starting from overcompensating for the deficiency. Good luck

potassium deficiency

Looks like she is wanting phosphorus and potassium . If it was a water issue the leaves would be a lot droopier. I think you went too long before providing feed or enough . Vegging npk ratio is 3-1-2.

They look like they need some oxygen, let that pot dry out between water and knock the light schedule to 18-6

1st I'd sort the light schedule to either 20/4 or 18/6 as 24hr is way to much. Also I'd add a calmag supplement to your feeds, I'm not familiar with your nutes but using LED lights usually means you need slightly more calcium and magnesium in the feeds then what most base nutrients contain.