CYA: Chemical OR Organic

Closed the pool last year at a CYA level hovering around 45....This year has been a nitemare as I deal with the green murky waters....
Several of the posters are trying to help by asking for my CYA number.....I went to grab that number today, only to have the pool store associate pull out a test strip for the test...With that, I walked out of the store....


I've gone ahead and ordered the R-0013 CYA test re-agent...Finally the question:

Why would I NOT assume that the CYA number of Fall/ 2007 would NOT be the same as June/ 2008 ?? I've added approx. 1000 gallons of water since opening and have NEVER used anything but liquid bleach... If anything, I would think the CYA number would be/ should be LOWER than last years 45PPM...

Reason for the post was in deciding how much PPM's should I be shocking to on order to fight off this algae issue...

Once CYA is in the water, it is reduced a little bit over the swim season by splashout, etc, but basically should stay the same over the summer. However, some people experience a lowering of CYA over the winter while the pool is closed (not all--Watermom usually loses some of hers, but I never do, even though my pool stays open during the winter, I don't change my routine much). Also, bad algae outbreaks have been known to completely break down CYA levels to zero. Personally, I'd chlorinate to shock level based on the CYA of 45 until you get a better number. Even if the CYA is lower, with a green pool, chlorine at the shock level for CYA 45 won't hurt.

Janet

I have to add new CYA every year.
The winter eats my CYA.

Its a mystery. There are theories as to why it happens but its still unsolved.

Me, too. Every year.