You definitely have an issue going, particularly the last photo, could be a few different things, so a question, are you adjusting your ph to 5.8? Quick tip, from @Bill284, put your cal mag in the water, mix, wait 15 minutes, add fox farm nutes, mix, wait another 15 minutes, then adjust ph to 5.8. Second question, are you using cal mag? I’d suggest using the fox farm Bush Doctor cal mag. What kind of water are you using, tap, RO, bottled? Do you check the ppm’s of the nute solution? Hopefully bill will chime in, he knows more about coco growing than I ever will.