Weed doctors to the rescue

You are in flower and at this point you really shouldn't have to be adding Cal/Mag. However, that is calcium deficiency which can be caused by low PH, or lack of calcium in your grow media. You have been feeding cal/mag, so I'd assume low PH. In soil, calcium is best absorbed by the roots in the 6.2 – 7.0 pH range (in soil, it’s generally recommended to keep the pH between 6.0 – 7.0, but calcium specifically tends to be best absorbed above 6.2) In coco or hydro, calcium is best absorbed by the roots in the 6.2 – 6.5 pH range (in coco/hydro, it’s generally recommended to keep the pH between 5.5 – 6.5, but calcium specifically tends to be best absorbed above 6.2) Flush with proper PH and PPM H20. In flower you should be trending to a higher PH than in Veg.