Just a little bit of haze, calcium hardness, and test result questions

Woody007

Active member
Aug 20, 2020
29
Midwest US
I had a little bit of haze and after testing the pool store suggested I add Hardness Plus, which I did, and it seemed to have done the trick. From what I've read, seems like adding Calcium wouldn't do that, but why did it seem to work?

This was my first visit to Leslies as my local shop was closed for the weekend.
Any ideas why would the test results vary so much from shop to Leslies? Whatever my shop does, they DON'T use the device that has the cuvettes in a carousel, but looks like drops added from a test kit of some type. These test were done a day apart.
Local shop numbers
alk 90
ph7.4
free and total chl 3.0
stabilizer 90
Salt 3300
hardness not normally checked, but two months ago was ~200

Leslies:
alk 65
ph 7.4
free and total chl 3.3
stabilizer 51
salt 2868
hardness 68
Phos 156 (is this high and need to be brought down?)

Is the methodology that different? I do trust the local shop as the water has been great for the 3 years they've been helping me, and they never push for more chemicals. Normally just a few bags of salt for the season. I'm not very experienced with the chemistry side since it's been pretty hands off for the last three years I've lived here. New liner this spring, so had to start new with city water.
Thanks for any suggestions.

Picture for reference. Pump on and a breeze, but looks pretty good to me.
20210705_205558690_iOS.jpg
 
Last edited:

Kellyp

Gold Supporter
Silver Supporter
Jul 5, 2018
196
Acworth ga
I guess I'll be the first to say it, but probably not the last......best advice we can give is get your own quality test kit. The TF-100 or the Taylor K2006C are the two TFP recommends and gives advice on.

Test your own water for reliable, repeatable numbers.
 
  • Like
Reactions: Dan7667

revitup

Gold Supporter
Bronze Supporter
Nov 30, 2019
645
Pawleys Island, SC
Pool Size
8500
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
They’re both pool stores. They’re likely both wrong. Get a quality test kit and do your own testing.
 
  • Like
Reactions: Dan7667 and Rich807

Woody007

Active member
Aug 20, 2020
29
Midwest US
They’re both pool stores. They’re likely both wrong. Get a quality test kit and do your own testing.
I guess I'll be the first to say it, but probably not the last......best advice we can give is get your own quality test kit. The TF-100 or the Taylor K2006C are the two TFP recommends and gives advice on.

Test your own water for reliable, repeatable numbers.
I guess you didn't have the opportunity to actually read my message before jumping on me for not doing my own testing.
 

YippeeSkippy

Mod Squad
Gold Supporter
LifeTime Supporter
Jan 17, 2012
17,628
Evans, Georgia
You can't test CH at 68. And the only way to go from 200 to 68 is if you drained a mess of water and refilled with very soft water.

Proof that Leslies is wrong, but not sure if your regular shop is all that much better??

But if your FC was truly only 3ppm THAT was your problem. Please follow the FC/CYA chart FC/CYA Chart
 
  • Like
Reactions: Rich807

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
14,044
Houston, Texas
To answer your question, I would trust the drop based testing before I would trust the machine/computer read testing. Computers need to be recalibrated frequently, and often read tests that require visual perception (such as CYA and CH) incorrectly. As for adding calcium, that alone would not clear up haziness. If it was a bag of calcium hypochlorite granules it contains both chlorine and calcium, and the chlorine may have been enough to clear the haze.

Now for the advice you did not ask for. Yes we do advocate that you test your own water. That is the best way to have consistent, reliable results. You may be blessed with a good local pool store that does proper, consistent testing, however most folks who visit TFP do not. I am assuming since you purchase salt that you have a saltwater chlorine generator. Based on the local store's CYA level of 90 ppm, that is a little high, and the free chlorine target range is 4-6ppm. I would adjust the SWG to increase chlorine production to reach 6ppm, and you shouldn't have any more problems with hazy water.
 

Woody007

Active member
Aug 20, 2020
29
Midwest US
To answer your question, I would trust the drop based testing before I would trust the machine/computer read testing. Computers need to be recalibrated frequently, and often read tests that require visual perception (such as CYA and CH) incorrectly. As for adding calcium, that alone would not clear up haziness. If it was a bag of calcium hypochlorite granules it contains both chlorine and calcium, and the chlorine may have been enough to clear the haze.

Now for the advice you did not ask for. Yes we do advocate that you test your own water. That is the best way to have consistent, reliable results. You may be blessed with a good local pool store that does proper, consistent testing, however most folks who visit TFP do not. I am assuming since you purchase salt that you have a saltwater chlorine generator. Based on the local store's CYA level of 90 ppm, that is a little high, and the free chlorine target range is 4-6ppm. I would adjust the SWG to increase chlorine production to reach 6ppm, and you shouldn't have any more problems with hazy water.
You can't test CH at 68. And the only way to go from 200 to 68 is if you drained a mess of water and refilled with very soft water.

Proof that Leslies is wrong, but not sure if your regular shop is all that much better??

But if your FC was truly only 3ppm THAT was your problem. Please follow the FC/CYA chart FC/CYA Chart
I appreciate your answers.
This is our 3rd season with a pool, and the local shop helped me keep it perfect so I never had any motivation to do my own testing.

This season we replaced the liner and started with tap water.
It cleared up nicely with shock. Added CYA and Salt, and had looked good. After a month or so it started to get hot here and the Chlorine level went way down and it got hazy.
Shocked it and it had been fine again for another couple of months and just started to get a little haze. The shop I normally go to was closed, so I thought I would go to Leslies and get some shock to repeat the previous process. The test results from them are what I posted earlier.
Trusting that they had a clue, I went with their suggestion to increase hardness rather than shocking, and it seemed to work, but that makes sense if their product has chlorine in it as well.
From your feedback it sounds like I need to increase the Chlorine level and maintain it a bit higher than I have been.
At night with the underwater lights on, I can seem some haze or particulate matter.
We did have a storm that blew tree debris in the water, and then rained for the next week. Is that enough to set off the imbalance that leads to haze?

Thanks again for your responses, and tolerance while I learn more about the chemistry of a pool. It's a bit confusing when I try to go with the liner manufacturer specs, local pool shop and forum feedback, but I'll figure it out.
 

YippeeSkippy

Mod Squad
Gold Supporter
LifeTime Supporter
Jan 17, 2012
17,628
Evans, Georgia
What is it you're adding when you call it "shock"?? How often do you add this when things are looking wonky?

How much chlorine do you think your pool needs daily? Do you know about the FC/CYA guide?? FC/CYA Chart
 

Woody007

Active member
Aug 20, 2020
29
Midwest US
What is it you're adding when you call it "shock"?? How often do you add this when things are looking wonky?

How much chlorine do you think your pool needs daily? Do you know about the FC/CYA guide?? FC/CYA Chart
It's liquid chlorine. I don't recall the brand, but in a yellow bottle.
I have only added this two times since April. Once when filling the pool to get the Chlorine up, and then once a several weeks ago.
I don't know how much it needs daily, but I have set the SWG to maintain ~3 ppm.
I have seen the FC/CYA guide, but it seems to want the Chlorine level to be much higher than the manufacture of the liner indicates.
Like my last post, seems to be varying information from different sources.
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
14,044
Houston, Texas
Here is some information about why TFP doesn't follow conventional recommendations. It may have more information than you need at this time, but it explains why we recommend the levels that we do.
We don't follow conventional pool industry recommendations. The problem with conventional recommendations is that they treat each chemical value as a separate entity that has no relationship to any other chemical value. For example, conventional recommendations only look at chemical values in their individual ranges, such as FC (chlorine) must be between 1-3ppm, without taking into account how other chemical values interact with each other. This is why they will say a CYA of 90 and FC of 2 are "perfect", because they both fall within the acceptable range for each value. However, CYA and Chlorine must be maintained in a proper ratio to each other. If you look at the FC/CYA Chart you will see that if CYA is 90 in a manually chlorinated pool, FC of 2 is far too low and algae will form under those conditions.

TA and pH are another example. Conventional standards want a TA of 90-120 and pH of 7.5 TA is generally only a concern when pH is difficult to balance. If you have a TA of 70 and a pH of 7.5 there is no need to adjust the TA just to meet an arbitrary value. If you do raise the TA to 90, then your pH is also going to rise. If you lower the pH the TA will also drop. pH can be 7.0 to 7.8 in most pools without causing further issues. There is no need to chase a perfect TA and a perfect pH if your pH is in the acceptable range and fairly stable. TA by itself means nothing.

pH and calcium also have a relationship to watch. Conventional recommendation for calcium is 250-450ppm and in most pools this is not a problem. However if you live in an area with very hard water it may be next to impossible to keep the calcium below 450. In that case it is important to keep your pH low, around 7.0, to prevent calcium scale formation in the pool.

Strictly following conventional recommendations can lead you to a pool full of problems if you don't know how the relationships between chemicals work. Knowing these relationships also guides what types of products to use in the pool. If CYA is high enough you don't want to use dichlor granules or trichlor tablets in your pool to provide chlorine. Both of these products contain CYA and will cause CYA to rise over time. The only way to get rid of excess CYA is to drain water out of the pool. It does not evaporate out with the water. Calcium hypochlorite adds calcium to the water along with chlorine. Like CYA, the only way to get rid of excess calcium is to drain water. Liquid chlorine is the only chlorine source that does not add either CYA or calcium to a manually chlorinated pool.
 

Enjoying this content?

Support TFP with a donation.

Give Support

Woody007

Active member
Aug 20, 2020
29
Midwest US
Here is some information about why TFP doesn't follow conventional recommendations. It may have more information than you need at this time, but it explains why we recommend the levels that we do.
We don't follow conventional pool industry recommendations. The problem with conventional recommendations is that they treat each chemical value as a separate entity that has no relationship to any other chemical value. For example, conventional recommendations only look at chemical values in their individual ranges, such as FC (chlorine) must be between 1-3ppm, without taking into account how other chemical values interact with each other. This is why they will say a CYA of 90 and FC of 2 are "perfect", because they both fall within the acceptable range for each value. However, CYA and Chlorine must be maintained in a proper ratio to each other. If you look at the FC/CYA Chart you will see that if CYA is 90 in a manually chlorinated pool, FC of 2 is far too low and algae will form under those conditions.

TA and pH are another example. Conventional standards want a TA of 90-120 and pH of 7.5 TA is generally only a concern when pH is difficult to balance. If you have a TA of 70 and a pH of 7.5 there is no need to adjust the TA just to meet an arbitrary value. If you do raise the TA to 90, then your pH is also going to rise. If you lower the pH the TA will also drop. pH can be 7.0 to 7.8 in most pools without causing further issues. There is no need to chase a perfect TA and a perfect pH if your pH is in the acceptable range and fairly stable. TA by itself means nothing.

pH and calcium also have a relationship to watch. Conventional recommendation for calcium is 250-450ppm and in most pools this is not a problem. However if you live in an area with very hard water it may be next to impossible to keep the calcium below 450. In that case it is important to keep your pH low, around 7.0, to prevent calcium scale formation in the pool.

Strictly following conventional recommendations can lead you to a pool full of problems if you don't know how the relationships between chemicals work. Knowing these relationships also guides what types of products to use in the pool. If CYA is high enough you don't want to use dichlor granules or trichlor tablets in your pool to provide chlorine. Both of these products contain CYA and will cause CYA to rise over time. The only way to get rid of excess CYA is to drain water out of the pool. It does not evaporate out with the water. Calcium hypochlorite adds calcium to the water along with chlorine. Like CYA, the only way to get rid of excess calcium is to drain water. Liquid chlorine is the only chlorine source that does not add either CYA or calcium to a manually chlorinated pool.
Thanks for that explanation. Makes sense about the relationship between the chemicals. I wish the manufactures would update their recommendations to reflect that. Being a relatively new pool owner with a new liner, I felt the need to do what the manufacturer recommends, but I'll start following TFP guidelines.
Attached are the results from weekly testing at local shop, and I added a column for TFP recommended targets. The first column targets are from the manufacture.
So looks like at my CYA levels, I need to increase my Chlorine levels about 2 ppm, right?

1625584919020.png
 

Woody007

Active member
Aug 20, 2020
29
Midwest US
Update, in case anyone cares, lol.
Local pool shop confirmed the CH was low. Brought it up to 350
Added 4 gallons of what I call shock, but is bleach from shop. Chlorine in the 5 range. I'll test it again next week to see where I'm at, but test just prior had dropped to 0.5 from a 3.5 couple of days earlier, so it was being consumed.
Water looks good like it did last year before starting over when the liner was replaced. I can see some particulates if I turn the lights on, but not bad at all.

Thanks for the feedback, and I will work to keep the Chlorine in proportion with the CYA going forward, especially with the new knowledge that higher Chlorine doesn't mean liner fade if in proportion with cya.
 
Last edited:

Webster

Gold Supporter
Jun 6, 2021
20
Nashville
Pool Size
29600
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite Pro (T-15)
My Leslie's store tests with a computerized system. It was broken for a few weeks and they tested with drops and entered the results in their system. They told me they prefer to do it this way because it's more accurate than the computer testing, but they have to use the computer for testing per corporate rules. So it's likely that your test results from Leslie's are inaccurate.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread