GrowCNanswered grow question 3 years ago Keep in mind that your pouring water on dirt so don't worry about "purified", bottled, distilled or reverse osmosis. I use my unfiltered water, from a well, which I Ph adjust to 6.5. The primary minerals in my water are calcium and magnesium in beneficial amounts so I view using Ph'd well water to be an improvement over filtered or RO water that had beneficial minerals removed.