Thank you both for thinking so hard about my pool. I have also been thinking hard and wanted to post something that may or may not be helpful. 1-2 years ago Baquacil developed a CDX system – to enhance oxidation. The instructions were for weekly maintenance - to poor the weekly dose of oxidizer ( 27% H2O2) in front of the skimmer followed by “CDX” into the skimmer which was supposed to help maintain the oxidizer residual. The ingredients are a combination of dimethyl and hydroxymethyl hydantoin. We used this system for the last 1 -2 years – and before that used oxidizer increaser tablets in the skimmer basket to battle the constant haze problem. I can get those ingredients as well if you think it might be helpful. But I post this info in case it might shed some light as to why my pool is behaving so differently and in case this chemical is potentially the culprit in creating the noxious chloramines?

I had meant to ask also if using a non chlorine shock might have a role at this point in my pool – but the percarbonate method sounds like it may be doing just that – oxidizing without chlorine? But thought I would ask since the non chlorine shock seems less time intensive, has less side effects, and is more readily available. I was thinking about whether I should add some chlorine to raise the CC levels, and then hit it with the non chlorine shock to kill them all off – I have no experience whatsoever on which to base this thought except of course the wracking of my brain to find a solution. Hoping you all could comment on it since you have the experience to back up your recommendations

In the way of an update, this morning at 1030 am my TC by OTO was just slightly more yellow than the 5 cell. pH was 7.5
FC was 5.5 and CC was 2 by FAS-DPD testing

At 4:30 the TC by OTO was less yellow than 5 but more yellow than 3 so I called it a 4
FC was 5 and CC was <0.5!!!! for the first time ever with a much less strong bleach smell than in the past.

My thought was to see what it did overnight – since the FC has held at five now for 36 hours and I haven’t added bleach in over 3 days – and re test in the morning. I want to see what happens when I add more bleach in terms of raising the CC levels again. I expect that it will raise the CC more than the FC if this process is still going on. I will be happily surprised if it does not – because that will mean this nightmare is over and we could actually swim in the pool! But it is rainy and cold here right now so we don’t feel too badly about missing out on the pool. Safety is our first concern. After I perform my little experiment to test my hypothesis I have no idea what I will do next - but may run it by you all! I am taking it one day at a time with this pool. Thanks again. aciam