Yes, foliar is great for a "get at the problem right now" solution. BUT,, as listed in his posts he has done this already and now needs to move on to the long term solution by adding a cal/mag supplement to his feed solution. Any supplementation/correction in a soil type grow will take 5-7 days to "show" in the plant.
Look at the pics again,,,,,I sure don't see any lockout!
Nizza is correct on the FF soil having Dolominte and oyster shell. But, Ace he mixed it with COCO and that needs extra Calcium just like RO does.