Hello. When I watered 3 days ago, I saw some brown...

FIRST!!!!! Yikes.... your pH is way, way, way too high! This has to get down to 6.0-6.5! Additionally, you're throwing a lot of different nutes at her and I have no idea why. Add to that, you've got at least 4 or 5 different nutes lines going into her all at once.... that's pretty much asking for problems as different nute lines don't always react well together. Chow_13's recommendation to just give them pH'd water for the next week or so doesn't really go far enough imho... you've got to get all those nutes out of there with a full flush - which won't be all that strenuous since they're still in solo cups - just run enough pH'd water through each cup until the runoff water tests between 6.0 and 6.5pH... (I hope you've poked holes in the bottom of those cups!) - then you need to decide on ONE nute line to use... and, at this stage of their growth, they really only need basic NPK nutes. The calmag doesn't have to be the same nute line as that is pretty much standard - but if you maintain a proper pH, the other nutes have enough calcium in them so calmag is often never needed... Don't go heavy on any nute that has a lot of nitrogen as too much nitrogen will induce a lockout and prevent the plant from taking up calcium or other nutes it needs. Good luck - get that pH down!!

Either watered while pot was wet or ph. Nothing else will bring those spots so early ...

Way to much food. Your ec/ppm should be half that. Down at 1ec/500ppm. Only pH water for the next few watering and it should stop. Damaged leaves will continue to worsen and prob die off. Look at new growth and unaffected leaves. Happy Growing