I don't know if this helps, but I went to the hydro store on Friday and got a 3-way meter - moisture, ph, light - for $10. It told me straight away that my PH was a little high. I also got advice in the noob forum that plain vinegar is a great way to lessen ph. 1/2 tbsp or such per gallon. You gotta measure your water. I'm using MG Organic and it's working OK. I've seen other people on here using regular MG soil with success, as well. I'm thinking your water, but I'm no scientist. FWIW, I know from home brewing (beer, mead) that water makes a BIG difference.