Good morning,

Search for a post from Michael Smith and download the calculator he has available in his signature. It has several very helpful calcs, including CYA, if you click on "more calcs" in the upper left hand corner.

Your losing a lot of FC so I'd think you are noticeably lower than 30ppm in CYA. To my knowledge, there is no harm in adding other items immediately after adding CYA. Others take a more conservative approach.

As you are probably aware, after you add the CYA, it will not show up in the test for a few days....mine took about 4-5 days if I remember. My assumption is that it takes that long to become completely effective as well so I'd go ahead and get it in there.

If my memory serves me correct, bleach has a pH higher than pool water....not lower. You've got a good handle on your numbers so I wouldn't change any of what you're doing but I don't think bleach was the culprit in lowering your pH.

If you've still got that little bit of algae and your CC tests a true .5 or more, I'd bring my FC up to about 12-15 and "shock" the pool. That'll get the CC to less than .5 and get the algae out of there, too.

Dave S.