CYA at 95

ElGuito

Active member
Jun 21, 2008
32
Hello all, I did a search for high level CYA and nothing came up, if this has been discussed please re-direct me. Thanks.
Darn "convenient" measuring strips, they showed 0 or very low CYA, so I added the cyanuric acid. After reading here that those strips are no good, I got a real test kit and the reading is CYA 95, I also read that the only treatment is to drain and replace water or use "untreated" liquid chlorine for a while.
I am guessing that it does not work this way, but if my CYA level is higher than ideal, will my chlorine remain higher and last longer?
I just hate to see all that drained water wasted and also water it is a tad expensive in my city.

Thanks all.
 

svenpup

LifeTime Supporter
Nov 18, 2009
835
Sacramento, CA
CYA helps protect chlorine from the sun, so it can help it last longer. The minimum FC level that you should maintain is determined by CYA level (link to chart in my sig). With CYA 95 (100) you should never let your FC get below 7 and you should target 12. The disadvantage with high CYA is that it becomes difficult to shock if it is necessary. You can see in the chart that your shock level is 39. :shock:
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
I suggest you replace enough water to get the CYA level down to at least 80. The CYA test is inherently a little vague, and reads levels higher than 100 as if they were 100. You are close enough to that boundary that your level might actually be much higher than you think.

Very high CYA levels do mean that you use less chlorine, even though the FC needs to be higher. But high CYA levels can be very problematic if you ever get algae.
 
G

Guest

There is one other way of dealing with it, ElGuito, but it is not available in all areas. Where are you located? I may be able to refer someone for you to consider, if it is an option.
 

anonapersona

TFP Expert
LifeTime Supporter
Nov 5, 2008
2,598
ElGuito said:
Hello all, I did a search for high level CYA and nothing came up, if this has been discussed please re-direct me. Thanks.
Darn "convenient" measuring strips, they showed 0 or very low CYA, so I added the cyanuric acid. After reading here that those strips are no good, I got a real test kit and the reading is CYA 95, I also read that the only treatment is to drain and replace water or use "untreated" liquid chlorine for a while.
I am guessing that it does not work this way, but if my CYA level is higher than ideal, will my chlorine remain higher and last longer?
I just hate to see all that drained water wasted and also water it is a tad expensive in my city.

Thanks all.
We talk about high CYA so often that the search function probably could not deal with it!

Yeah, you will need to go to using bleach or "liquid shock" which is just stronger bleach for your chlorine for awhile. Depending on CH levels and the pool surface, you may be able to go to cal-hypo for chlorine. It can be economical if you get the huge buckets from Leslie's but not if you use the pre-measured 1 lb bags that cost 3 or 4 times as much.

CYA will drift downward over time. It will depend on whether you get enough rain to make the pool overflow or if there is enough splash out to lead to adding fresh water. Evaporation won't help as it leaves solids behind.

Probably drain and refill is still best, unless you are going to get a lot of rain over the winter. What is your location?
 

ElGuito

Active member
Jun 21, 2008
32
Thank You All for the prompt replies. I decided to drain and add new water. Some of the other threads mentioned draining until water level drops 1 foot, so I did it to 1 1/2 for good measure.
After refilling, the CYA test shows 65, yay!
I am in Orange County, Southern California so my only consideration was cost of water here, the city charges for the water consumption and the cost of pumping it up to us.

Thanks!
 

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