Yellowing and Spotting - Diagnosis Please

I didn't se thte chemicals initially, but struggled for a couple weeks to get the PH down. Equal parts of the HG Aqua Flakes A and B were likely used, and the PPM was at 575. The PH was up around 6.5 more than it wasn't so I'm guessing that a slightly high PH was causing some key nutrients to get locked out...anyone else concur with this diagnosis?

I have recently got aggressive and lowed the PH, decided to add a strong GH solution to increase the overall PPM to 750-800. Hopefully this will help.

Also, I'm guessing that up until recently the majority of the roots were still withing the 4" rock wool cubes that were a bit on the wet side due to the constant drip...so maybe they were "over watered" as well (though now the roots are surely venturing out more and this will no longer be a problem, if it was at all).

move ur light closer for one. the second image shows stretching good luck on your grow though. usually overwatering causes drooping which your plants dont seem to do. what strain is it?

Mostly P-91 and one Purple Kush

Also, the clones were stretched when I got them...I have a 400MH over 7sq feet of space...more than enough, even if the light is 18' above the plants.