Deficiency advise

I think your top growth color doesn't actually look bad...and you don't want it to be either too dark or too pale. But maybe the pics don't fully show how you're seeing it. For the rust spots, they mostly make me think of calcium, especially how they're mainly on the outter part of leaf where the light touches. They say calcium is best absorbed around 6.2 but i don't completely agree with that. Maybe this plant is just extra calmag hungry, which can vary strain to strain. If you're feeding a good regimen and the ph is correct for the medium, the only thing I'd say is recalibrate your ph pen for accuracy. I also usually keep my ec down a bit lower between 1.2-1.4 but everyone has different success numbers. Good luck with the problem solving.✌️