I've fucked around with coco perlite and peat a bit. pH is usually stabile right where you want it unless you don't transplant and force your plants to stay in small pots, then I find the soil gets rancid and the pH fucks everything up. But if you transplant and flush when your plants need it it's all you need. I just use it strait out of thew bag, never reuse it though. A bail will last you all year for $25 where as small walmart bags will make you throw away $100's a year.