Possibly a Cal mag def.

Hi so I am in the begining of week 6 of Veg and was planning on flipping my girls to flower in 6 days. I just noticed these brown or looks like purplish spot in some of the bottom leaves and a few of the top leaves. I’ve done some research and I think it’s a calcium magnesium deficency. Can anyone confirm if this is correct?

this is happening on both my GDP and Pineapple Express plants.

I was watering with a half gallon of well water until week 5 then noticed they were drinking more so I upped to it 3/4 of a full gallon and kept the nutrients the same. Increasing the dose every feeding until I get to a full dose.

feeding schedule: water,feed, water, feed, water.
Water every 3 days because that’s when the fabric pot gets light and feed every 6 days to not cause nute burn or lockout.

grow info:
Soil: Fox farm ocean forest, fox farm light warrior, perlite.
3 gallon fabric pots
Nutrients:
GDP
Big Bloom: 1 1/8 tsp
Grow Big: 1/2 tsp (FULL DOSE)
Cal-Mag: 1/2 tsp (FULL DOSE)
Si-Armor: 1/2 tsp (Full Strength)
Ph: 6.54 ppm 672
Runoffh 6.98 ppm 632

Pineapple Express:
Same soil as GDP
Nutrients:
Nutrient watering:
Big Bloom: 2 tsp
Grow Big: 1/2 tsp ( full dose)
Cal-mag: 1/2 tsp (full dose)
Si-Armor: 1/2 tsp (full strength)
Ph 6.52 ppm 742
Runoff: ph 7.00 ppm 727

the full dose are according to what the bottle says but its for a full gallon and I am doing 3/4 of a full gallon.