I'm in the process of filling our pool with water from a municipal water source and it looks good so far. I decided to test the pH to see where I'd be and it came out 7.5. Just right. I also decided, out of curiosity, to test for CH. Not a critical factor, as it's a vinyl Intex pool and I plan to use the BBB method, but I do have some CalHypo left over from last season and I was curious about using it and the risk of raising my CH. Well, after using the CH test from my TFTest kit, I finally got some blueish water after close to 50 drops. Is it possible that my water source is in the 500 ppm range? That seems very high to me. I hope I was testing properly. Any thoughts?