Can anyone help with this?

So I’m in Day 13 of 12/12 And this is happening but I can’t figure out if it’s calcium issues or something else.. here’s the deets

Botanicare silica blast Advanced nutrients connoisseur bloom a+b (non coco version) sensi mag 50% strength bud igniter 1/4 strength botanicare sweet raw 1/4 strength
Total ppm 750 and I’m using tap water
Day temps 80 night around 70. I have been battling humidity with it sitting around 70-80% for a few weeks but have purchased a dehumidifier and has since got to down to 50-60%

Medium is botanicare coco grow with perlite mixed in..

Runoff is always lower than what I put in so I’m confused cuz it looks like nute burn but at time ppms will be between 390-420ppm and doesn’t that mean they are eating well? Could it be caused by the the high humidity? It also looks like potassium or potassium Deficiency from ive been seeing from my google searches... could it be that?

Could be light stress? I’m running a fluence bioengineering spydr at 100 percent but raised to the top of the 4x4 tent..
Any help is appreciated !!

Well what was the outcome? Did you feed it more usually way higher ppms come out with the run off.

Ended up being a cal mag situation but that particular plant ended up being a hermi at the end anyway but two others did make it through ... these two