Hi all, Paul here,
Found a lot of great advice here. Just switched to bleach (from tri-chlor in skimmer baskets) and I'm slowly adding 20 mule team borax. Approx. 15 ppm (calculated, not measured). Using 6-way HTH strips and a very old guardex 4-way test kit for now. Pool is crystal clear (for now). Can count the shedding plaster grains on pool floor 10 feet down.
Thanks for this site.