Using Bleach

[Watermom]

I have a hard time believing that your CYA is only 37 if you are using that many trichlor pucks. Typically new members who have been using a chlorinator come here with sky-high CYA levels. It will be interesting to see what your CYA level is when you test it yourself with the K-2006 (or 2006C) kit.

Your pH is too low. The fact that most likely your pH tester doesn't differentiate any values lower than 6,8 means that it may likely be lower than that. Any pH below 7.0 is acidic and can damage your pool. Add a half a box of 20 Mule Team Borax (laundry aisle at Walmart) slowly to the skimmer while the pump is running, breaking up any clumps. Wait a couple hours, retest and redose until you get your pH between 7.2-7.8.

If you go to using bleach, you'll be able to test and add bleach in the evenings only. For reference, in a 15K gallon pool, each quart of 6% bleach will add 1ppm of chlorine. That will help you know how much bleach to add each evening when you test. Again, we need an accurate CYA reading to know what levels of chlorine you'll need to run. As Ben said, read the Best Guess chlorine chart in one of our signatures.

Welcome to the Pool Forum!

[PoolDoc]

Watermom, please note that readings like CYA=37 usually means digitally read 'guess strips', which in turn usually means bogus dealer testing.

As you know, the best real test are, at most, plus/minus 10ppm . . . and strip based CYA testing tends to be plus/minus 30 - 40 ppm. So, when you see impossible results like 37 -- instead of 30 or 40 -- it means the digital reader is 'making up' the extra digits so the test results look much more accurate than they really are.

Ben

[Watermom]

Yeah, I know. That is why I said he needs to get a kit and test it himself so we will know what his actual CYA really is.