Need help with CYA level

[Hachu]

Hi,

Please help with lowering CYA level. I've been given different info on ways to lower CYA level and I'm not sure which is best for my pool. This is a new pool that was built in December 2019. Pool Builder said to never empty the pool completely, but one pool technician/maintenance said to empty the pool, brush/power wash to get all the cya that is stick on the pebblesheen first then refill. I'm nervous about having too much chlorine in the pool to keep up with high cya level. My kids have sensitive eyes and eczema.

Test Kit: Taylor K-2006C
Temp: 96°F
Nice clear water
FC -11.5
CC or TC - 0.2
pH - 7.4
TA - 70
CH -
CYA - way above 100. I can't get an accurate reading above 100.

Thank you

 

[mknauss]

Draining - Further Reading

www.troublefreepool.com

There are risks in draining a pool. One is ground water, will the shell pop out of the ground? The other, in the summer, is the plaster overheating and popping/cracking.
The statement to power wash the surface to remove CYA is hogwash. CYA is in the water. Not embedded in the plaster. Power washing a plaster surface can easily damage it.
The article above explains differing methods to drain or exchange your water. Read through it and come back with which way you feel it is safest to achieve your goal.

Have you done an extended CYA test? See Step 8 in CYA - Cyanuric Acid Test - Trouble Free Pool

 

[YippeeSkippy]

Do you know how all that CYA got into the pool?? Lowering to aprox 80ppm would be an ideal time to add a Salt Water Chlorine Generator and get rid of that dispenser and Ozone (oh no zone!) device. Have you considered doing that?

Salt water pools are great for folks with skin issues.

Maddie

 

[Hachu]

Thank you!

 

[Hachu]

Do you know how all that CYA got into the pool?? Lowering to aprox 80ppm would be an ideal time to add a Salt Water Chlorine Generator and get rid of that dispenser and Ozone (oh no zone!) device. Have you considered doing that?

Salt water pools are great for folks with skin issues.

Maddie

Hi Maddie,

All pool builders we spoke to advised us not to get a salt water pool due to damaging equipments and to furnitures.

I believe our last pool maintenance guy added too much? I test my pool on regar basis (after a day or two after pool guy does it). One week it just shot up way above 100 and it's just been high since. Could there be any other reasons CYA just get high?

 

[jimbethesda]

All pool builders we spoke to advised us not to get a salt water pool due to damaging equipments and to furnitures.

Hogwash! Buy this salt test kit and see what your salt is already up to.

Amazon.com : TAYLOR TECHNOLOGIES INC K-1766 DROP TEST CHLORIDE SALT WATER : Swimming Pool Liquid Test Kits : Garden & Outdoor

Amazon.com : TAYLOR TECHNOLOGIES INC K-1766 DROP TEST CHLORIDE SALT WATER : Swimming Pool Liquid Test Kits : Garden & Outdoor

www.amazon.com

 

[Hachu]

Draining - Further Reading

www.troublefreepool.com

There are risks in draining a pool. One is ground water, will the shell pop out of the ground? The other, in the summer, is the plaster overheating and popping/cracking.
The statement to power wash the surface to remove CYA is hogwash. CYA is in the water. Not embedded in the plaster. Power washing a plaster surface can easily damage it.
The article above explains differing methods to drain or exchange your water. Read through it and come back with which way you feel it is safest to achieve your goal.

Have you done an extended CYA test? See Step 8 in CYA - Cyanuric Acid Test - Trouble Free Pool

Thank you! I really like the exchange water method. I'm hoping I can do that. I will also try to do the extended CYA TEST method to see if I can get a better CYA amount.

 

[mknauss]

Sounds good. Read that section carefully. Depending on water conditions and/or water temperatures determines the process you use.

 

[Chasarms]

Mix 50% pool water with 50% tap water. Measure the CYA using your test kit. Then multiply by 2 to get the value.

You need to know how much water to drain before just randomly doing it.

 

[Hachu]

I did the extended CYA test and I got 135 (I couldn't decide between 120 or 140 depending where I stood to read it). How do I calculate how much water to exchange?

 

[mknauss]

If you drain 2/3 of the volume, your CYA will be just below 50 ppm. A good spot to be.

If you plan to use the exchange method, part of that is measuring your outflow rate. With that, you can determine how long you need to run the exchange. I would add about 10% more exchange volume as the process is not perfect.

 

[Hachu]

Silly question..the article stated make sure pump is off while doing the exchanhe....that means just have everything turned off (switching the system to Service Mode) right?

 

[mknauss]

that means just have everything turned off (switching the system to Service Mode) right?

Correct. You do not want the pool pump mixing the waters.

You can add a bit of liquid chlorine to the inflow to be sure the waters are kept chlorinated.

 

[Hachu]

Ah thank you! I was just going to ask what chemical I would need to add while the water exchange is going on. I'm guessing water water/chemical balancing will need to be done afterward, too? Will there be a need to do a pool start-up like if it was newly added water?

 

[mknauss]

Once you are done with the exchange you turn on the pool pump, brush the pool really well, and after a few hours do a full set of tests. From there you see what you need to adjust.

 

[Hachu]

Correct. You do not want the pool pump mixing the waters.

You can add a bit of liquid chlorine to the inflow to be sure the waters are kept chlorinated.

How much liquid chlorine should I add and how often should I add while filling? My garden hose is pumping about 5 gallon/minute, so it'll take about 24-25 hrs to complete the exchange.

Is it safe to pump effluent water into the backwash ptrap(it has an opening so i can just put the house in) located at the front of the house?

 

[mknauss]

Add a half gallon of 10% throughout the process. I use my sewer clean out for my effluent water.

 

[Hachu]

Should I perform a backwash right after the water exchange is completed? Or a filter clean?

 

[duraleigh]

Should I perform a backwash right after the water exchange is completed? Or a filter clean?

No reason to do either. You are exchanging clean high-CYA water with clean no-CYA water.

Don't overthink this process and don't get all bogged down in the details of what happens next.

1. Exchange your water. remove 2/3 as Marty suggested

2. Post a set of test results and we'll offer advice from there.

Easy Peasy

 

[Hachu]

Thank you. I always tend to over think things. I have about another 3.5 hrs left of exchanging. Then, I'll turn pump on and brush really good. Wait about 3 hours and do a complete test.