What deficiency?

Are you following there feeding schedule for your plants? https://livingsoilsfertiliser.com/pages/feeding-regime Adding in extra oyster shell flower is good for calcium but will throw your PH off. It's mainly calcium carbonate and not in an available form for plants to readily uptake. I would lower your PH down a bit if that nutrient line allows for it. in the 6.2 range. I would still mix in a bit of the Grow formula like 1/5th of it vs the bloom. 2% nitrogen in flower is to little I feel. Despite the small claw tips on the top of the plant, indicting an over feeding of N. This stuff looks and feels a Lot like Gaia Green, If you added in extra Calcium go and add in a bit more Magnesium as well. 1tea/5ml per gal on next water. "I use Epsom salts" The leaves look like calcium and potassium deficiencies but you have plenty of potassium and calcium, so PH/availability is probably the issue. Best Of Luck!