New Pool Owner - Testing Myself

[Cohnhead]

Hi. We just bought a house with a pool (pebble) and spa and this is our first pool we have ever owned. The pool was built in 2018. For the first few weeks of when we moved in, we continued to use the pool maintenance company. They were horrible so I fired them, which is ok because my plan was to take over the maintenance myself anyway. So I just got my TFT Pro test kit and these are the results I got. I also got the test from the pool store free testing, but these are my results:


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Test Results 10-26-2022 @ 09:24 PM

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Free Chlorine: 8.0

Combined Chlorine: 0.0

pH: 7.8

Total Alkalinity: 90

Calcium Hardness: 261

CYA: 100 (the pool store said it was 174)

Temperature: 62°F


My question is do I need to drain the pool all the way to fix the high CYA level? Or just 1-2 feet?

The pool store also said there were high Phosphate levels. Is this something I need to be testing as well?

 

[Texas Splash]

Welcome to TFP! You can ignore the pool store's comments and concerns for phosphates. Your CH number seems to be a pool store number and not from your TF-Pro kit, so you might want to validate that one. As for the CYA, it is a bit concerning since it's difficult to maintain the correct (corresponding) FC level per the FC/CYA Levels. Before you go any further, I would recommend doing a diluted CYA test of your own. Use the link below starting at Step #8 to see if your CYA truly is over 100 and by how much. Let us know what you get, and also take a moment to update your signature with all of your pool and equipment info. That info can influence our recommendations. Thanks for posting.

CYA - Cyanuric Acid Test

Cyanuric Acid (CYA) is the chemical name for what is commonly referred to as Stabilizer … Read more…

www.troublefreepool.com

 

[Mdragger88]

Do the diluted test first as @Texas Splash mentioned.
Then you will know where you stand. To reduce cya by 50% you will need to replace 50% of the water with fresh water- it’s directly proportional.
Here’s some info on safely exchanging water

Draining - Further Reading

www.google.com

 

[Cohnhead]

Thank you for the information, @Texas Splash and @Mdragger88. Of course, I came down with the flu after I wrote this, so I will do the diluted test in a day or two and let you know what I find out. I will also get my signature updated with my pool info.

 

[Cohnhead]

Welcome to TFP! You can ignore the pool store's comments and concerns for phosphates. Your CH number seems to be a pool store number and not from your TF-Pro kit, so you might want to validate that one. As for the CYA, it is a bit concerning since it's difficult to maintain the correct (corresponding) FC level per the FC/CYA Levels. Before you go any further, I would recommend doing a diluted CYA test of your own. Use the link below starting at Step #8 to see if your CYA truly is over 100 and by how much. Let us know what you get, and also take a moment to update your signature with all of your pool and equipment info. That info can influence our recommendations. Thanks for posting.

CYA - Cyanuric Acid Test

Cyanuric Acid (CYA) is the chemical name for what is commonly referred to as Stabilizer … Read more…

www.troublefreepool.com

I did the diluted test and the results came back as 160 cya. Also, the CH were my results, not the pool store. I verified that. For the CYA, how much of my pool do you think I need to drain?

 

[Texas Splash]

I did the diluted test and the results came back as 160 cya.

Just to confirm .... so your diluted result was 80 multiplied by 2 (=160) correct? If so, then you'll want to exchange enough water to get the CYA down to about 70 or below. You have a cartridge filter, you unless you have a waste spigot after the pump or some other outlet after the filter to remove water, you'll want to use a separate/sump pump to exchange water. Simple math, changing half the water reduces the CYA in half. So if you exchange half the pool, your CYA should go to about 80. A CYA of 80 is more than you need this time of year but much more manageable for sure. If you have any questions let us know.

 

[Cohnhead]

Just to confirm .... so your diluted result was 80 multiplied by 2 (=160) correct? If so, then you'll want to exchange enough water to get the CYA down to about 70 or below. You have a cartridge filter, you unless you have a waste spigot after the pump or some other outlet after the filter to remove water, you'll want to use a separate/sump pump to exchange water. Simple math, changing half the water reduces the CYA in half. So if you exchange half the pool, your CYA should go to about 80. A CYA of 80 is more than you need this time of year but much more manageable for sure. If you have any questions let us know.

Yes, it was 80 multiplied by 2. We do have a spigot on the system. But I am going to buy a submersible pump and drain it that way. Based on those numbers I found, I probably need to drain a little more than half of my pool. Does that sound right?

 

[Texas Splash]

Does that sound right?

It does. Just be careful about how low you go in case you received a lot of rain recently and/or may have a high water table in your area. We want the pool shell to remain stable. Always best to be safe. Good luck!

 

[Bcorig]

Wow! That's a monster CYA level.
Do you care to share what led to the decision to suspend your business with your pool guy?
When I took over I spent another year relying on unreliable results from the pool store but still did OK.
Now I very recently obtained my own K-2006-SALT testing kit and am completely on my own. Should have done that a year ago.
Hang out here. You'll learn more in 2 days than you did in 6 months with your pool guy.

 

[Cohnhead]

I had not planned on keeping the pool service anyway, but there were a few things that sped up my decision.

- I asked them to go over all the pool equipment with me and they said they would set up “pool school.” After asking two more times to set this up I gave up trying
- I called to ask for parts (a light went out, and the heater wasn’t working). They said they would get back to me. Again, I had to call before they told me the parts are on back order. There was no communication at all.
- the first time I emailed about the heater not working, they responded with the diagnosis (air pressure regulator) within 30 minutes. Considering they didn’t even come and look, that sounded crazy to me. I asked how they determined that and there was no response. But my pool heater is working fine now. There does not appear to be anything wrong with it.
- overall, I felt like they were not doing anything worth paying for and since their communication was so bad, I decided to fire them.

 

[Gary Davis]

As you're well aware, you want your CYA level to be much lower than it is because just to be effective, your chlorine level has to be at least 7.5% of the CYA level (example, CYA of 100 ppm means you need 7.5 ppm chlorine just to begin to be effective).

What's a good CYA level to aim for? Depends on you but most would start worrying at around half the CYA levels you're reporting.
Your ideal CYA level depends a lot on whether you're using pucks or liquid chlorine (as pucks raise the CYA level but liquid chlorine does not).

For me, I keep my CYA levels low, so for me, anything above 15 ppm to 30ppm is approaching too much but I am well aware others easily keep it double (or even triple) that CYA level without worrying about how much it decreases the effectiveness of the chlorine even as it increases the effectiveness of the sunlight UV degradation.

As for your TA:CH ratio of 90:260, it's my personal opinion that's not bad at a bit lower than a 1:3 ratio at about 60 degrees given these are the three of the half dozen critical components of the saturation index which determines whether you will be etching or scaling or balanced. Personally I'd raise the calcium to at least the 1:3 ratio with inexpensive dissolved calcium pellets (or even aim for a 1:4 ratio - but always keep in mind the saturation index is a function of a half dozen factors).

Please especially note that the ratio isn't the important part. It's just a ballpark figure to make it easier for you to keep in mind that there is no one set of numbers that determines a balanced saturation index but a few ballpark ratios help you to manage the half dozen components of the saturation index.

If necessary, I can provide references for all my statements above (just ask in the DM system).

 

[Cohnhead]

Ok, I’m almost done with the drain/replace of the water. I did (based on my math) replace 75% of the water and it has been raining. What are my next steps once it is full? Should I turn the pump on once it’s full? Or should I test the water fully first? I’m not sure what to do next.

 

[mknauss]

Circulate using the pump for a few hours and brush the pool well. Then take a sample and test. Adjust FC and pH. Post your chemistry data for any other adjustments.

 

[Cohnhead]

Results are in. Here are the new numbers:

Latest Test Result Summary:

FC: 1.5

CC: 0.5

pH: 7.5

TA: 40

CH: 100

CYA: 60


Can you offer me recommendations on what chemicals to add? I was hoping my cya would have gone down more, but I guess 60 is ok.

 

[PoolStored]

Great job on getting the pool square!!!!

Get some FC in there by adding Liquid Chlorine...now. Follow this chart and keep it in the recommended range for your CYA (this is a link) -->FC/CYA Levels

Download pool math, enter your results, it will tell you what to do. While you are learning, ask and confirm your addition here...don't just blindly follow pool math --> PoolMath

Re-read this --> Pool Care Basics

 

[Cohnhead]

Ok. I can’t tell you how much I have learned in 2 days in this forum! Thank you for all the help. So I added my results in Pool Math and this is what I have come up with:

1) It’s telling my how much bleach to add based on chlorine percentage. If I go get bleach, they say on the back: “sodium hypochlorite 7.5%” “other 92.5%” and “yields Chlorine-7.1%” Is this what I can add to the pool and use the yields chlorine to figure out the percent bleach chlorine for pool math?

2) Aalso add approximately 8 lbs. of baking soda to raise TA

3) add 58 lbs of calcium chloride? I am not sure where to get this. Is this also a common household item?


And can I add this all at the same time?

 

[mknauss]

Is this what I can add to the pool and use the yields chlorine to figure out the percent bleach chlorine for pool math?

Use the 7.5% in Poolmath.
Add the baking soda.

You do need some CaCl2. Your CH should be 250 ppm minimum. You can get that at pool stores, off Amazon, etc.

 

[Gary Davis]

Ok. I can’t tell you how much I have learned in 2 days in this forum!

To keep it simple, the main thing, IMHO, to keep in mind is there are TWO main chemical entities to deal with in an outdoor pool.
1. Sanitation (this is "mostly" a function of your CYA and FC levels, where minimum FC is 7.5% of CYA)

Chlorine / CYA Chart​

2. Saturation (this is often called "balance", and is often described as "aggressive", "balanced" or "scale-forming" water)

Calcium Saturation Index (CSI)​

Thank you for all the help. So I added my results in Pool Math and this is what I have come up with:

Keep in mind, surprisingly, the sanitation is a function mostly of CYA & FC but not pH (for an outdoor pool).
Just as surprisingly, keep in mind the saturation is greatly influenced by temperature (where temperature is out of your direct control for an outdoor pool).

What's surprising to most people is the pH, while it influences almost everything, really only plays a major role in the saturation index (for an outdoor pool).

Unfortunately for simplification purposes, the pH is a complex function mostly based on inevitable equilibrium with carbon dioxide in the air.
However, the TA sets a ceiling for the pH just as borates (if any) can set a floor.

TA - Further Reading​

Borates in pool - Further Reading​

And keep in mind that saturation also takes into account TA, CH (carbonates, specifically), CYA and TDS to a lesser extent.

1) It’s telling my how much bleach to add based on chlorine percentage. If I go get bleach, they say on the back: “sodium hypochlorite 7.5%” “other 92.5%” and “yields Chlorine-7.1%” Is this what I can add to the pool and use the yields chlorine to figure out the percent bleach chlorine for pool math?

I described the math from Richard Falk over here, which allows you to determine which type of chlorine has the most bang for the buck in your area.

What are your go to chemicals to balance?​

2) Also add approximately 8 lbs. of baking soda to raise TA
3) Add 58 lbs of calcium chloride?

Here's where things get a bit complicated because what matters is the saturation index, not specifically how much TA or CH you have per se.
There is no magic number. What matters are a combination of a half-dozen factors, some of which are dependent on your fresh water supply.

Luckily raising your TA and raising your CH is just about the easiest and least expensive things you can do to your pool water.

Total Alkalinity​

Calcium Hardness & Ice Melt​

I am not sure where to get this. Is this also a common household item?

You can get fifty-pound bags of 94% pure calcium carbonate online shipped to your door for about a dollar a pound.

Snow Joe CaCl price doubled, what product do you use to raise your CH?​

And can I add this all at the same time?

While there are some pool chemicals you never want to add at the same time (such as bicarbonate & soda ash within hours of adding a chloride product).

How much Calcium can I add at a time to a pool?​

In that video I just linked to, Bob Lowry says it's ok to add 100 to 120 ppm of calcium chloride at a time, but bear in mind the exothermic reaction requires you to add only about five pounds at a time to a five-gallon bucket of water at a time.

 

[Cohnhead]

Is the SnowJoe ok to use for CH? The TF article on CH warns about using ice melters due to added salt.
Added bleach and Baking soda last night around 11pm
Today at 3:30 pm, my levels are:

FC - 8.0
CC - 0
PH - 8.0
TA - 80
CH -125
CYA - 48 (approximately)

Current plan - Add Muriatic Acid for PH, add SnowJoe for CH?

 

[Newdude]

Is the SnowJoe ok to use for CH?

I don't like the 94% pure. There can be alot of devil in those details. It might be rock salt, it might be iron.

Plus, SnowJoe is sold out this moment on amazon with an unknown resupply date.

I like puritech. It's a few bucks more but still fairly generic. It's worth it for the 100% IMO.

https://www.amazon.com/Puri-Tech-Calcium-Hardness-Increaser/dp/B012B9HU8W/ref=mp_s_a_1_5?crid=1S9MXSEQZKTTG&keywords=puritech+calcium+hardness+increaser&qid=1667340038&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ%3D%3D&sprefix=puritech+ca%2Caps%2C117&sr=8-5