m0useanswered grow question 6 months ago Does look to be beginning of calcium issues forming.
BioBuzz does not recommend anything under 6.2PH for their feeding regime. I'd lower your feeds and keep up with the CaMg supplementation. When growing in soil I find its best to feed once a week and water the rest of the days, especially if your not getting any runoff with it. If you are getting a bit of runoff, then it might be time to get a bit more and prevent the salts from building up in the medium.
https://www.biobizz.com/wp-content/uploads/2020/03/Nutrient-Schedule-EN-2020.pdf
Their feed chart.
https://420life.com/wp-content/uploads/2021/10/Marijuana-Leaf-Deficiency-Chart-scaled.jpg
A nice leaf chart
Good Luck!