Thanks for everyone's help here. That link to the AFN post is particularly helpful: (feed/ flush/ feed/ flush)
I think the ultimate problem here is my watering technique. I normally pour my water EXTREMELY SLOW and get little or no run off water. 3 quarts of water in a 3 gallon pot and no run off, hmmmm 🤔 . I think any extra stuff in my soil just wasn't flushing away and this led to the nitro problem.
I did "faster" watering so I can actually get some run off and check the PH (5.8. Low but not "dangerously low"). That faster watering must have flushed something out. The next day I saw that nothing else has dried up (that big leaf in the pic looks exactly the same), nothing else as turned yellow and the tops of the plants are "praying" again!
I'll continue with nutrients in a day or so, sticking to Bloom nutes and trying to keep the nitro a little lower.
Thanks again everyone! (Except for the Q scammer. Seriously. Leave that kinda drama to FB)