Pro-mix BX? I'll stick with the Pro-mix HP for now as you are going to lose some of the porosity via amendments. Looks to me like the Happy Girl online store's purchasing agent went a little overboard with a Pro-mix order and now they have to clear out inventory. In any case, some of the statements regarding hydroponic growing are fanciful. Pro-mix requires no pH adjustments, a chimp could grow plants with it. Rockwool, however, does require pH management but that is hardly much of a burden and the increased yield more than makes up for the extra efforts required indoors.