Is it only pH that is inaccurate during SLAM?

[2thdoc1]

My PB opened our pool yesterday. Water is dirty but fairly clear. Yay! I wasn’t sure how much bleach he put in, but I tested it tonight and FC is at 24, CC is <0.5. I know pH test won’t be accurate, but what about rest of tests? TA? CH? CYA? Thanks!

 

[mknauss]

TA test can be effected. The others, not so much.

Read - Trouble Free Pool

 

[ajw22]

Depends on your CYA. If your CYA is 0 then the TA test can bleach out.

Test your CYA then let’s see where you are.

 

[2thdoc1]

Thanks!! Waiting for water sample to warm up a bit and then going to test CYA.

 

[mknauss]

Thanks!! Waiting for water sample to warm up a bit and then going to test CYA.

Did the PB add any? It does not occur naturally in water.

 

[2thdoc1]

He did not add any this season- last fall at closing it was 80 (we have a SWG, fiberglass pool.

 

[2thdoc1]

CYA is at 50 so I will need to bring that up a bit. Should I wait until FC goes down before adding it?

 

[ajw22]

Your signature does not show a SWG. Why do you want the CYA above 50?

 

[mknauss]

Sorry - when you said PB I figured this was a new pool.

You can wait on the CYA for a while if you like.

 

[2thdoc1]

No problem- it was new last August so PB includes the first closing and opening in the price. I’ll wait until FC drops down (it’s above SLAM levels by 4 ppm with current CYA) and then add stabilizer.

 

[mknauss]

The FC level has no effect on when to add stabilizer.
In your climate, your FC demand will not rise until later in May to June. But you can add CYA whenever you wish.