So I run the Jack’s at; A 3.78, epsom .99 and B 2.52 grams per gallon. Those are their numbers brought down from 100gals to 1. I have about a 40 gallon reservoir and my tap water is 55ppm (.1ec). I’m going to mix a tank tonight and I’m going to bump it up from the 12 gallons I was mixing for, up to 15 gallons. Should give me about 400ppm (.8ec). So 15 times 3.78, 15 times .99, and 15 times 2.52 plus some Cyco PH adjusters and that’s it in my tank except for 40 gallons of water.
Without a pic it’s hard but you mention a mag excess. The 1.2 you list is high for the epsom in Jack’s; it should be .99 grams a gallon. There’s more mag in the part A. I run a little less than the .99 in veg; probably closer to .6 or .7 g per gallon. I just went up to .99 the last tank since they’re getting bigger and I need to flip.