Ghost Train Haze #1 micro grow

That looks more of a burn to me. Is you diary accurate with a EC of 3.6?? If so this is all burn from over feeding. 3.6 is way to high. You need to flush that substrate and fix your concentration. I'd go down to 1.8EC max but flush with plan water PH'd to 6.4 then added in nutrients once they are out of the medium. Magnesium deficiency does not tend to curl and burn the leaves, it does make it yellow though or light green. It can also make stems look more red but this is also shared with Phosphorous deficiency. Check out a leaf chart for cannabis for more information. https://420life.com/wp-content/uploads/2021/10/Marijuana-Leaf-Deficiency-Chart-scaled.jpg Good Luck!