Hey there so I am having a very similar issue with a set of plants, started green and strong and slowly leaf symptoms like calmag, iron, zinc etc. I tried increasing the calmag like you and still no results. I see you don't have a ph listed? When i finally tested mine i found it was way outside the limits of the 6-7. I suggest checking that, either by pen, strips, or even a soil test(they have sticks and sets at the garden store). If you don't want to ph the water you can either add soil acidifier(thats a dry amendment) if the soil ph is too high. Or to raise the soil ph you could add some form of lime, like oyster shell lime which also helps with the calcium in the soil.
Good luck with the problem solving ✌️