Plant bleaching

Did you change your pH suddenly from 1 feed to the next? Do you know the pH of your soil?

Raise your light or dim it a bit if you are concerned about light burn. Though light burn typically shows on the very top of the canopy. Your affected leaves aren't at the top of your plant so it leads me to believe that it's something else. You have no diary to reference, and you've not given any info as to your feeding, pH, Environmental numbers. Without more details it's way harder to get a sense of your plant and what that could be.

I wanted to add this happened overnight. I also installed a more intense light 3 days ago.