CYA

[RowdyC]

I've drained and refilled and have the CYA at what I think (kit shows up today or tomorrow) is a workable level.

Q. Throughout the summer, will CYA levels be affected by evaporation? That question has been driving me nuts for a week

 

[harleysilo]

Yes, as you refill lost water your CYA will go down.

 

[RowdyC]

Thanks! I just didn't know chemically speaking if CYA would be a part of the evaporation process or if it separated from the water evaporating and remained in the pool! Thanks again.

 

[Richard320]

I've drained and refilled and have the CYA at what I think (kit shows up today or tomorrow) is a workable level.

Q. Throughout the summer, will CYA levels be affected by evaporation? That question has been driving me nuts for a week

Not really. CYA doesn't evaporate. For illustration, let's say your average pool depth is 50 inches (makes easy math). If you let the level drop 2" before refilling, that's 4%. If CYA was at 50, it's now at 52. You probably won't see that change on the tester view tube. And when you refill it to bring it back up to 50" deep, CYA will be back at 50.

The only way you lose CYA is by splashout, what sticks to people when they get out of the pool, and what you lose when backwashing. Remember, you're measuring parts per million. That's pretty small. 50 ppm is only .005%

 

[thehowheels]

Thanks! I just didn't know chemically speaking if CYA would be a part of the evaporation process or if it separated from the water evaporating and remained in the pool! Thanks again.

CYA does not evaporate. You can reduce your CYA by draining / backwashinig, or through splash-out. There are some reports of pool owners experiencing unexpected CYA loss after closing and re-opening, but it is definitely not typical.

 

[RowdyC]

Thank you both! I'm trying to convert a neglected "pool store" pool into a BBB pool. So as I'm trying to be patient, I'm thinking about things such as this CYA thing. Thank you. And BTW, we just bought the house and pool in November, so I'm NOT the neglectful party.