Tabs aren't bringing up my CYA

[sunpole]

I've been using tabs to supplement bleach for 2 weeks. I drop 3 tabs a week, so 6 tabs so far. For my pool size, 6 tabs ~ 12 ppm of chlorine and 7ppm of CYA. And I have been testing CYA twice a week, but noticed no change. For full disclosure, I may have added about 15 minutes worth of water via garden hose to compensate for regular water loss.

I was under the impression CYA doesn't go down by itself unless you dilute it with water. But it seems to me there is some sort of burn off of CYA, does this have to do with high temperature? My pool temp has been hovering around 90F.

 

[JimMarshall]

What was your CYA prior to the tablet additions?

IMO, 7 PPM CYA is within the limits of normal testing error.

 

[jblizzle]

Yeah, the cya test is plus or minus 10 PPM if you're good at it.

 

[Catanzaro]

The 7 ppm CYA increase is to minor for you to really see that on the test. Assume it is there and test once a month. If testing is done twice during each week you could possibly run out of the solution. Test once every two weeks if there are enough 3" tablets that are dissolving. In addition, you also may lose a little bit of CYA each month, but with the testing you will be fine. Always target your minimum FC based on 10 ppm higher than what you always test for CYA.

 

[sunpole]

What was your CYA prior to the tablet additions?

IMO, 7 PPM CYA is within the limits of normal testing error.

I started out 40 CYA, and plan to get to 50 via tabs then I would stop. In term of $/chlorine, tabs are about 40% cheaper than bleach for me.

- - - Updated - - -

The 7 ppm CYA increase is to minor for you to really see that on the test. Assume it is there and test once a month. If testing is done twice during each week you could possibly run out of the solution. Test once every two weeks if there are enough 3" tablets that are dissolving. In addition, you also may lose a little bit of CYA each month, but with the testing you will be fine. Always target your minimum FC based on 10 ppm higher than what you always test for CYA.

Agree, I probably went a little overboard with CYA testing. I might have been a little too cautious with tabs from reading this forum, lol.

 

[Wulfdan]

With water that warm you will see some CYA loss.