Pro mix is very low in any newt value and there two different types that are mainly used for MJ, HP and BX I believe, depending on which one you go with you may have to add D lime to help maintain the PH and you do need to feed plants with additives more frequently with Promix, but it can work very well, most people use it in what you call a soilless mix, it is boarder line hydro. For good results IMO I would look for the Fox Farm Ocean soil which some use all the way threw a grow with no additives, but it is best when used with the Fox Farm additives, Big Grow, Big Bloom and Tiger Bloom. Right now I am using Black Gold Potting soil which many folks go with as a matter of fact I think I saw a post by Garden Knome stating that he uses it and loves it. My mix is 75% BG and 25% perlight with SuperThrive, Liquid Karma and when I go to flower I think that I will use FF's Big bloom. The good thing about Black Gold is that most stores carry it.
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