Most people dose both Mg and K2SO4 only at water change time to a specific target. I believe the wording of 2-4 times door EI is intended to refer to macro and micro dosing, not GH booster minerals.
I would reduce your Mg to 5 ppm and add both that and your K to your water change water. You may need more if using RO or tap is low, but too much can cause issues too. Neither of those are very active or chelated, so you don't have to worry about them like you do with P or Fe.
For K, don't forget you get a lot from KNO3 and some from KH2PO4. So adding K2SO4 to that should get you to those levels. Here's my current dosing for reference (high tech):
Macro (x3): 24 NO3, 15 K, 6 P
Micro bottle (x4): .6 Fe, .2 Mn, .18 B, .2 Zn, .006 Mo, .008 Cu, .002 Ni
Water change: 14.3 Ca, 3.3 Mg, 20 K
Last edited by natemcnutty; 10-06-2018 at 09:42 PM.
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