How long should I expect stabilizer and chlorine to last in Texas heat?

[cu0ngpitt]

Hi,

I live in TX and it’s been a crazy hot summer with consecutive 105+ degree days.

I’m only on my 3rd yr off pool ownership and am confused as what to expect on how often I need to check and add stabilizer. Almost everywhere, you read that stabilizer NEVER breaks down and water must be diluted to lower CYA levels. If this is true then how come I have to maintain my stabilizer levels over the months/years?

I found this thread (Can't keep my CYA levels up Texas heat is making me lose my mind) which says I should expect to lose 10 ppm over a month or two.

I’d just like some clarification on what is correct in case there’s something wrong with my pool chemistry. Also read that ammonia can be an issue if you can’t maintain chlorine levels.

At the beginning of this summer, I balanced my CYA to 40 ppm. It’s been 3.5 months and I’ve rechecked it and I’m now down to ~20 ppm (this is a guess bc the Taylor kit doesn’t go below 30).

Also, I have to add 1 gal of 10% chlorine to the pool every 1-2 days during the summer to maintain levels above 5 ppm. Is this also expected in this type of heat? Again, asking to make sure I’m maintaining things correctly.

 

[ajw22]

CYA - Further Reading

www.troublefreepool.com

In general, once you add CYA to pool water it will be in the water unless you drain the water that contains the CYA. Some CYA is lost as water splashes out from pools.

Water leaking from pools will take CYA with it. Unexplained dropping of CYA levels, especially if you have an auto-fill automatically adding fresh water to the pool, can indicate a water leak.

Evaporation of water from the surface of the pool will not cause a loss of CYA. The water will evaporate and the CYA will stay in the remaining water.

High pool water temperatures will cause the chlorine to oxidize Cyanuric Acid. This tends to show in water temperatures of 90+ degrees. Every 10F increase in temperature results in roughly doubling the rate of degradation.

Chlorine breakdown in sunlight causes CYA degradation by hydroxyl radicals. This can cause a loss from 2 ppm per month to 10 ppm per month depending on the amount of sunlight the pool is exposed to.

In an area with 90+ pool water temperatures and extreme sunlight exposure 10+ ppm of CYA a month can be lost through degradation.

 

[ajw22]

Also, I have to add 1 gal of 10% chlorine to the pool every 1-2 days during the summer to maintain levels above 5 ppm. Is this also expected in this type of heat? Again, asking to make sure I’m maintaining things correctly.

1 gal of 10% chlorine will raise FC by 9ppm in your 11,000 gallon pool.

That is enough for 2 days of FC loss in the Texas sun. Especially if you have low CYA.

I suggest you keep your CYA between 40 and 50 in the summer heat and check CYA at least monthly.

 

[woodyp]

50 minimum on the CYA around Herr. Just the sun and heat of the water can eat 5 ppm a mo th of cya.

4 ppm loss of FC daily at that cya level is typical this time of year. DON'T ride the minimum # of FC recommended now. A couple points over that is fine to drop down to.

 

[cu0ngpitt]

I haven’t swam much this year so it’s def not the splash out and it’s so hot this year here (don’t have an auto fill feature) I’ve had to top the pool off once every week/other week.

Based on what I’m hearing this sounds normal for my area and I should be checking my CYA levels a little more often and keep it between 40-50 ppm.

Thanks!