Of all the Taylor tests, the cya to me is the most subjective. (ph being the second but much easier) To me the problem is when does the dot really disappear? I know that may sound stupid but it does get very hard to see before I assume it totally vanishes. I called taylor and they said "when you can see it anymore."

I think my issue is I still need more cya. The best I can make out, it's just below 30ppm. I have added some liquid pricy stuff from Leslie's Pool Supply. I then added 2 4lb bottles of dry cya. (from Lowes - age of cya uncertain does it weaken with age & storage?) To my 14400 gallon pool. My CL seems to be stable overnight but during the day I will loose about 2ppm. Would getting my cya closer to 50 help? Currently I'm using straight bleach but last year I reverted back to a combination of pucks and bleach.

A few years ago I had a very high cya level (around 120?) I drained the pool half way and got it to be around 50 - 60. The beginning of this year I checked it (same kit) and it was barely hazy (well below 30ppm) That sounds impossible because Iv'e heard cya just can't disappear.