@teddy bonkers look long and carefully at my avatar until you feel the vibe.
Definitely looking like some P deficiency but signs of others lacking as well so I'd go with higher ppm but cut way back on the CalMag. Your humidity is such that your plants aren't drinking enough to pull up adequate nutes so a higher ppm will help with that. I deal with very low RH most of the time so run lower ppm.
I trust my nutes to have a decent supply but as I use RO or distilled water only I do add some CalMag once in a while and at no more than half the recommended dose. That's in DWC but with soilless ProMix HP and hydro nutes I rarely add any as the media has lots.
CalMag is not the magic pill that a lot people think it is.