Criteria for Replacing Pool Water

[sparcel]

What would be a good summary of the levels of CYA, Calcium Hardness, Sodium (for non-salt pool), or other stats, that would suggest need for at least a major water replacement?

Not just for me, but for everyone's reference.

For me, given the droughts in California, I have not even considered replacing our water in years. It has actually been well over 20 years. But given all the rain we have had this year it seems like if I am anywhere close to needing to replace it, 2023 is the year to do it.

In my case, my CYA is only 30-40, so I know that is not a concern. My Calcium Hardness is ~350, so that seems ok. I have not yet measured my sodium level. Anything else to test for this purpose?

 

[PoolStored]

What would be a good summary of the levels of CYA, Calcium Hardness, Sodium (for non-salt pool), or other stats, that would suggest need for at least a major water replacement?

Not just for me, but for everyone's reference.

For me, given the droughts in California, I have not even considered replacing our water in years. It has actually been well over 20 years. But given all the rain we have had this year it seems like if I am anywhere close to needing to replace it, 2023 is the year to do it.

In my case, my CYA is only 30-40, so I know that is not a concern. My Calcium Hardness is ~350, so that seems ok. I have not yet measured my sodium level. Anything else to test for this purpose?

This is highly dependent on a bunch of factors, environment (level of evaporation, amount of rain), how you manage your pool (backwashes, drain to waste, autofill), chemicals in your input water, etc. etc.

Any reason why you are concerned about salt? If you can't taste it, or it doesn't bother you if you happen to taste it, then don't worry about it.

 

[sparcel]

I only asked about salt because I have seen posts on TFP that suggest high levels, such as > 5000ppm, can be a reason to replace water. I don't know what my level is, but likely way below that. More broadly, if possible I thought perhaps others on TFP might like to see a summary of the criteria for replacing water.

 

[PoolStored]

I only asked about salt because I have seen posts on TFP that suggest high levels, such as > 5000ppm, can be a reason to replace water. I don't know what my level is, but likely way below that. More broadly, if possible I thought perhaps others on TFP might like to see a summary of the criteria for replacing water.

Ahhh...gotcha.

So the 5000ppm is typically for those that have a Salt Water Chlorine Generator. At higher levels of salinity (generally >5000), the cells will stop working. The only way to get the salt out is to replace water. In a liquid chlorine pool, salt levels don't matter, unless you can taste it AND don't like the taste.

On the summary criteria, it is so variable you would have to create a very complex tree. Take the example above. If you have an SWG, then 5000 might be to much. If you have an older cell that doesn't shutoff you might be ok. In a non-SWG pool, salt levels don't matter.

Most of the level information for each, for those that are interested are embedded in the WIKI. Examples:
Calcium Hardness (see the "Managing High CH Levels" section here:

Calcium Hardness - Further Reading

www.troublefreepool.com

 

[an1vrsy]

This question is for your pool specifically. With all the rain that has happened in California, do you have an overflow on your pool? If not, how many times have you had to lower your pool water level manually this winter?

 

[sparcel]

Ahhh...gotcha.

So the 5000ppm is typically for those that have a Salt Water Chlorine Generator. At higher levels of salinity (generally >5000), the cells will stop working. The only way to get the salt out is to replace water. In a liquid chlorine pool, salt levels don't matter, unless you can taste it AND don't like the taste.

On the summary criteria, it is so variable you would have to create a very complex tree. Take the example above. If you have an SWG, then 5000 might be to much. If you have an older cell that doesn't shutoff you might be ok. In a non-SWG pool, salt levels don't matter.

Most of the level information for each, for those that are interested are embedded in the WIKI. Examples:
Calcium Hardness (see the "Managing High CH Levels" section here:

Calcium Hardness - Further Reading

www.troublefreepool.com

Wow, I'm surprised it is such a huge decision tree. For an in-ground, gunite, non-SWG pool like mine, it there still a huge decision tree?

For my pool, beyond CYA and Calcium Hardness, (and Sodium if I don't like the taste) what other components of pool water can sometimes force the need to replace the water - even if the criteria cannot be practically stated? Nitrites? Something else?

 

[sparcel]

This question is for your pool specifically. With all the rain that has happened in California, do you have an overflow on your pool? If not, how many times have you had to lower your pool water level manually this winter?

I have had to lower the pool water level several times. Maybe a total of 12-18 inches. I might not have needed to pump off quite as much if I was not concerned about the keeping the water level not excessively high (but that is another issue). Certainly it would have overflowed if I had not pumped off at least 6-12 inches.

--scott

 

[PoolStored]

Wow, I'm surprised it is such a huge decision tree. For an in-ground, gunite, non-SWG pool like mine, it there still a huge decision tree?

Just follow the recommended levels and you should be fine!

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

For my pool, beyond CYA and Calcium Hardness, (and Sodium if I don't like the taste) what other components of pool water can sometimes force the need to replace the water - even if the criteria cannot be practically stated? Nitrites? Something else?

Nothing really, as long as you use our recommended pool chemicals...

Recommended Pool Chemicals

Which should I buy? TFP's recommended pool chemicals are cheap, easy, and won't unbalance your pool water.

www.troublefreepool.com

And avoid non recommended chemicals...

Non-Recommended Pool Chemicals

These pool chemicals should not be added to your pool. Save your money and frustration and avoid these chemicals!

www.troublefreepool.com

If you use some not recommended chemicals they can add copper (staining, etc.) and sulfates (equipment damage) among other other bad stuff. Well water can add iron, which can cause staining.

If you stick to recommended chemicals there is little you have to worry about...

Hope that helps!

 

[YippeeSkippy]

I would venture that you may have exchanged more water than you know considering all the rain you've rec'd this year.
Calcium, Salt and CYA are the elements that remain in a pool when evaporation removes water or you drain x amount and refill with fresh tap water. You can lose them with splash out but they remain for the most part. Due to this when Calcium, Salt or CYA levels become too high draining, replacement is almost the only time we recommend.

 

[Mdragger88]

More broadly, if possible I thought perhaps others on TFP might like to see a summary of the criteria for replacing water.

It is in the wiki

Draining - Further Reading

www.troublefreepool.com

 

[sparcel]

It is in the wiki

Draining - Further Reading

www.troublefreepool.com

Thanks! I see it mentions "Does the pool water have salt in it above 2000 ppm or a Calcium Hardness of 800 ppm or more?". I'm a little unclear how this intended to be interpreted given the exact context where it is mentioned in the article, but I assume it is suggesting that salt above 2000 or CH above 800 would be a reason to drain (except I assume in a SWG pool re the salt level). Of course opinions vary, but salt above 2000 seems maybe a bit contrary to the opinion earlier in this thread re: only if it bothers you.

I see it also mentions high ammonia as a reason to drain. I find this a little confusing given this article seems to show you can lower it using chlorine. Ammonia - Further Reading. Perhaps in locations with cheap and plentiful water people drain more casually?

--scott

 

[PoolStored]

Thanks! I see it mentions "Does the pool water have salt in it above 2000 ppm or a Calcium Hardness of 800 ppm or more?". I'm a little unclear how this intended to be interpreted given the exact context where it is mentioned in the article, but I assume it is suggesting that salt above 2000 or CH above 800 would be a reason to drain (except I assume in a SWG pool re the salt level). Of course opinions vary, but salt above 2000 seems maybe a bit contrary to the opinion earlier in this thread re: only if it bothers you.

Those questions are not for WHY you drain, but the importance of TDS in determining where to drain. Salt and high CH lead to high TDS. Continue the article to "Pump from the deep end or near the surface" section...

I see it also mentions high ammonia as a reason to drain. I find this a little confusing given this article seems to show you can lower it using chlorine. Ammonia - Further Reading. Perhaps in locations with cheap and plentiful water people drain more casually?

Yes. Even the "swap" drain is dependent on the situation. It costs me $2000 to refill. Chlorine was $5/gallon. I could go through 400 gallons of bleach before I hit break even. There are lots of nuances to many situations. There are also more than one way to solve many of the problems we see.

 

[ajw22]

Thanks! I see it mentions "Does the pool water have salt in it above 2000 ppm or a Calcium Hardness of 800 ppm or more?".

That is a criteria in HOW to do the No Drain Water Exchange process and not WHEN to do it.

I see it also mentions high ammonia as a reason to drain. I find this a little confusing given this article seems to show you can lower it using chlorine. Ammonia - Further Reading. Perhaps in locations with cheap and plentiful water people drain more casually?

It can take 10pm of chlorine to clear 1ppm of ammonia.

Where water is inexpensive and chlorine is expensive draining can be the most cost effective option.

 

[PoolStored]

Where specifically is that mentioned?

First paragraph of 3.5 No drain water exchange...

Draining - Further Reading

www.troublefreepool.com

 

[ajw22]

First paragraph of 3.5 No drain water exchange...

Draining - Further Reading

www.troublefreepool.com

Yeah, That is a criteria in HOW to do the No Drain Water Exchange process and not WHEN to do it.

 

[PoolStored]

Yeah, That is a criteria in HOW to do the No Drain Water Exchange process and not WHEN to do it.

Yes, we both said that in my post #12 and your post #13. Are you confusing me with the OP maybe? I was just answering your question "where did you read that..."

 

[ajw22]

Not just for me, but for everyone's reference.

Seems to me "everyone" who follows TFPC Methods rarely has to replace water in their pool other then those in high CH fill water areas.

 

[sparcel]

Seems to me "everyone" who follows TFPC Methods rarely has to replace water in their pool other then those in high CH fill water areas.

Though I assume many who want to start following TFPC methods, who already have very high CYA, will likely want to replace much of their water.

 

[ajw22]

Though I assume many who want to start following TFPC methods, who already have very high CYA, will likely want to replace much of their water.

People come from all different places to get into the TFP groove. That is why we find it is better for folks to start a thread with their specific situation then try and follow some generic advice.