What’s happening? Wow yep mid to high 90’s is smoking for indoors without co2 so are the runoff numbers but don’t chase runoff numbers. Runoff contains chemical salts from nutes plus fine sediment from soil so it’s an inflated number anyway but yeah if your pen is correct the numbers are off the charts. If you start tweaking your feed ppms to get better runoff numbers then you can hit the wall, as much as I hate saying it a flush might be in order but looks like phos def maybe and perhaps mag def. mag powers up chlorophyll
What kind of soil? Did you amend it? What kind of nutes? Are you using cal-mag? Have you added any recent top dress? Are you adjusting ph? To what value? What size container? Are those fabric pots? How long have they been in those containers?
Last one I promise, walk us thru the process - how do you mix your nutes?
I know that’s a lot of questions but it helps to know. Your plants look good, sorry this happened
maybe hold off on flush for a day until we can see your answers