I bought a KegLand pH meter and decided to test it out before my brew day this weekend. It's my first pH meter, so I needed to figure it out. I have the storage solution and pH 4.0, 6.86, and 9.18 buffer packets. I mixed up 2 buffer solutions (4.0 & 6.86) each in 250ml of distilled water. Then I calibrated in both buffers. After doing that, it was accurately reading the buffer pH for both solutions. Then I tested the pH of the last beer I brewed which I suspected was slightly acidic. The measured pH was 3.96 which seems right to me. Then I measured a Sierra Pale Ale and it read the pH to be at 4.35. again that seems pretty accurate to me. Finally I went back and measured the pH of the distilled water I used to make my buffers. The measured pH was 5.2 which I was not expecting. I thought it would be neutral at 7.0. Are all my readings off because of this? Anyone else using distilled water for their buffers? I know it said to use deionized water, but that stuff is pretty expensive.