CYA Questions

[BigBri594]

Hello Everyone,

Opened the pool at my new place for the first time on Saturday, and with the help of the people in these forums, I have everything balanced and the water looks great! Two questions concerning CYA:

1) My pool is at least 30 years old and the previous owner has been using chlorine tablets the entire time. I was expecting to open and have a huge CYA problem, but that was not the case. My CYA was only 30. If the tablets are so discouraged because they increase CYA, then how could a pool which has only been chlorinated with the tablets still have a low CYA?

2) I had planned on using only bleach, but the previous owner left a whole container of trichlor tablets. Since my CYA is on the lower end (30), is there anything wrong with using the tablets? Of course I would keep an eye on the CYA and switch back to bleach should the CYA climb too high.

Thanks for the help!

Brian

 

[Texas Splash]

To answer your questions Brian:
1 - Hard to tell. Some areas in the NE avoid the dreaded "high CYA" either because of a relatively shorter swim season, amount of water exchange, or other factors. If it's low, consider yourself fortunate.
2 - You have a TF-100 and can accurately test CYA to within +/- 15ppm. So as long as you are in control, you can use the pucks for a while to ensure the CYA doesn't creep-up on you. Also remember pucks are acidic so they may impact (lower) your pH a bit. So be aware of that as well.

Hope that helps.

 

[ship of fools]

I am in upstate NY and my CYA disappears every winter. Each season i add enough to get to 30 PPM.

 

[kris77]

I was helping a friend open his pool this weekend. Last year he had CYA of 35 or so. He opened this year and his pool just wouldnt clear up. It stayed cloudy no matter how much bleach he added. He tested everything but CYA. I tested it and it was 0 as well. It all went away over the winter. We bumped it up to 35-40 and the pool cleared up in a matter of hours. Dont know where it went or why it was gone, but it was. Now its looking great.