hey pawt
I've only used MG soil, but its the "Moisture Control" pkg. its NPK is .21/.07/.14...now there is some thing I dont like, it has twigs & pieces of bark but thats what I started with 4 yrs ago before I put them in the ground & after loseing trees to hurricanes & floods, I grow out of pots now... I know it can be done & I do not have a green thumb!... hell if it was a plant & i touched it it will most certainly die... I also use perlite in the MG soil.
I also use MG nutes, the same ones you are useing along w/superthrive...

here is a pic of the clones that i kept in my kitchen during the winter in MG fed by MG under house hold floro lights..
if you need any info let me know... but I am a beginner like you...
M.