your medium mix wants to me light, airy, fluffy with little to no nutes in it. Stay away from the MG stuff, it has time release nutes and will be difficult to control. Get yourself some manure/humus mix or if you can find it, i found this stuff that is like black gold to plants, its called Black Earth and all i have to do is add perilite to it and its done. If you have a hydro store nearby you can get a bag of Fox Farms Soiless mix and that will do y ou right also. Just make sure that you dont get medium that has peat in it, you will have to adjust your pH alot if you do and can be a pain in the butt.