I just bought an MW101 pH meter, and I plan to get serious about my water treatments. As part of the process, I'm going to have to keep the meter calibrated, of course, and the testing/buffering and storage solutions aren't cheap. I'm thinking about using a couple of old White Labs vials to hold the testing solutions while I calibrate. Does anybody see an issue with calibrating in such a relatively small container? Also, can I cap the vials and reuse the calibrating solutions again? If so, would you recommend limiting to a specific number of "reuses"?