Hi everyone, I have a situation and I'm hoping that someonem might have some insight. I have a pool in N. California. I discovered that my pool company raised the CYA to 100. I was concerned that I'd have to keep the chlorine at about 10ppm, but the pool company says they want it at 5ppm or below. *But*, my Taylor FAS-DPD kit showed 20ppm.

The management acknolwedged that they super chlorinated it for some reason, but it would be safe to swim in it up to 25ppm. A week later, I told them that the levels were still 16ppm+. I asked what reading they had from their recent visit, and the guy told me 3+. Huh? I asked how they could have such a low number against my high reading. He said their kits don't go above 3, but they have fresh reagents, and that my kit might be old. So I could go buy a Guardex kit to compare.

The next time the pool guy came by, I asked him about it. The night before I read 10ppm. He said he read about 3 and showed me his kit. It was an older looking one with yellow gradients, it stopped at 3. He said he can tell when it is higher by the deepness of the color. So, I'm wondering if his kit might only measure active chorine, and thus be correct if the CYA is inhibiting the free chlorine. Or are they totally off? BTW, they are a very established service in the area for the past 30 years.

Any feedback would be great!