I'm not to sure but have this to add. I once took a water sample from a tank to Aquatek for a monthly test. After swirling it around with a few chemicals the guy doing the test looked right at me and told me I have a water softener. We did at the time. I asked him what that was supposed to mean, mentioning it to me, and he did not have a real answer. He implied it was bad but would not commit to anything.