These two threads:
http://www.poolforum.com/pf2/showthr...hlorine-Locked
http://www.poolforum.com/pf2/showthr...il-to-chlorine
seem to be both products of an issue I don't remember dealing with before: pools with a LONG history of Baquacil use, before conversion.

I talked with "Aciam" at length last night, and agreed upon the following:

#1 - Test with OTO ; ignore FC / CC differientiation
#2 - Dose to dark yellow (~10ppm); allow it to drop to medium yellow (~2 ppm)
#3 - Continue filtering 24/7
(Aciam's water is clear, but some sort of surface debris is forming continuously and being collected on her skimmer sox)
#4 - Dose with polyquat that the FIRST signs of algae (slippery sides on Aciam's vinyl AG pool)
#5 - If no resolution after a few days, consider drain and refill (AG pools ONLY!)

My **guess** is that there's a huge accumulation of Baqua-goo from the years of Baquacil use, and that -- whatever else Baqua-goo is, chemically speaking -- it is very resistant to chlorine oxidation. The high CC levels are a result of slow (but sure) oxidation by chlorine.

What's weird is that her FAS-DPD readings did NOT match her OTO test results at all. I trust OTO more than DPD, so I made the recommendation above. However, I had to tell her I really have no idea how cleanup will take. I've emailed Chem_Geek to see if he's collected any info on this.

Ben

PS: It sounds like "reesie" is in the same situation. Ben