Not sure about your tank, but I normally do 50% weekly water change. So for me ei seems better for me. However I only dose half of ei in my tank, if I dose full ei algae will become uncontrollable.
My tank 15G extra long and shallow. Fully covered by plants but no tall stem plant.
Personally I follow part of EI, most part of my dosing scheme customized according to my plants reaction.
I think AT FIRST GLANCE the difference between pss Pro and ei is that ei give nutrient in abundance and maintain at certain level through water change while pps pro provide just enough and thus no need to do large water change.
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