I'm with 9finger on this one.
Although having the ability to fine-tune your mix to compensate for different feeding needs of varieties, I find that it's overly complicated.
I run Jacks 3-2-1(5-12-26 base w/micros, CalNit, and Epsom Salt) and have really good results in all of the medium I grow in.
The only modification I do during the run is to replace 1-1.5 g/gallon of the 5-12-26 with an equal amount of MKP(0-52-34) as a phosphorous booster during stretch.