Hi aylad,

The product I've been using is Aqua Chem Shock Plus. I'm not at home right now so I can't post the ingredients, I can do that later if it would be more helpful. I don't think it has changed the CYA because that has stayed pretty much right on the mark since originally added the stabilizer to get it up to 40ppm.

In all honesty the chlorine has probably been yo-yoing up and down, I have only been working on it once a day, sometimes twice. What threw me off was that I did not get any kind of reading.... period after adding 3lbs of this aqua chem product just a few hours after adding it to the pool, nor again the following morning. The reason I stopped using liquid bleach is because it seems they have quit making Ultra Bleach, I can never find it anywhere. Is there really much of a difference between that and the regular bleach? Thanks again.

All the Best,
Merrick