Hi, that's great that you figured out the source of the diarrhea, and thanks for sharing this information. It is so true that sometimes it's really hard to pinpoint just what is causing reactions, illness, or symptoms in our bullies. Many wouldn't have thought of water as a source of diarrhea, good job mommy. My daughter had a water softener in her old house, that was put in place by the builder, as they also had hard water. They were notified and advised not to drink the water from the soft water tap, because the chemicals used to soften the water are a known carcinogen, and also there is a lot of sodium in soft water. Another tip I find helpful when determining what our bullies are allergic or sensitive to is to add one new food, treat, or supplement at a time, and by itself, so if there is some kind of a reaction, you will know right away what caused it.