CH test

Nikilyn

Bronze Supporter
Sep 3, 2018
1,129
Gilbert, AZ
Pool Size
17000
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Is this the correct blue color? I realized I've been doing it wrong after reading posts on here about it. I was reading it at purple. So I went to blue this time and my number went way up to 725. At what level should we drain it? Is draining the only way to get the CH level down? We've only had the pool since February and we even had to drain some water off because of rain. I'm not real keen on replacing water every 6 months. 7EF7484B-5BC9-46D8-A403-EA1F7DD8D4D8.jpeg
 

mknauss

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TFP Expert
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May 3, 2014
44,424
Laughlin, NV
Pool Size
6000
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Fiberglass
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Pentair Intellichlor IC-40
Those blue floatys mean you have some metals in your water. Do the fading endpoint process to see if that makes the endpoint easier to see. Go to Testing Directions in Pool school.
 
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Nikilyn

Bronze Supporter
Sep 3, 2018
1,129
Gilbert, AZ
Pool Size
17000
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Those blue floatys mean you have some metals in your water. Do the fading endpoint process to see if that makes the endpoint easier to see. Go to Testing Directions in Pool school.
I'll do that test tomorrow. Should I take water to Leslie's to find out what metals are in my water? Does this mean we need to drain?
 

Nikilyn

Bronze Supporter
Sep 3, 2018
1,129
Gilbert, AZ
Pool Size
17000
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
A CH of 725 is elevated, but by no means any reason to panic. You can continue to balance the water and compensate for that CH by keeping a close eye on the pH and TA. The PoolMath APP is perfect for that so you can monitor your CSI.
Pool Math says my CSI levels are fine. I watch pH closely because we use our waterfall quite a bit. I check TA every couple of weeks. I just checked it today and it's starting to go up. It's currently at 90.
 

SecoSteve

Silver Supporter
Jul 28, 2020
139
Lincoln University, Pa
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Plaster
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Jandy Aquapure 1400
Is this the correct blue color? I realized I've been doing it wrong after reading posts on here about it. I was reading it at purple. So I went to blue this time and my number went way up to 725. At what level should we drain it? Is draining the only way to get the CH level down? We've only had the pool since February and we even had to drain some water off because of rain. I'm not real keen on replacing water every 6 months. View attachment 372144
I have the same issue. My sample will look like it turns blue while on the SmartStir, but if I hold it up to the light, it is like lavender. I have to keep adding drops to get a true blue. This is our first season with this pool too, and I can't imagine my CH is that high. I take a sample in to the store at the recommendation of the PB every once in a while just for comparison, and the CH that they report is in line with my "lavender" result.

I've just tested my brother-in-laws pool water, as they have just gotten a new pool, and his sample turned true blue with first color change, so I feel my reagents are good. I am on well water, so I must have metals in the water. Fading endpoint process gives the same result.
 
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mknauss

Mod Squad
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Bronze Supporter
May 3, 2014
44,424
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I'll do that test tomorrow. Should I take water to Leslie's to find out what metals are in my water? Does this mean we need to drain?
No need to test for metals. Probably a very small amount of iron. See what the fading endpoint test shows. You do not need to drain.
 
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Nikilyn

Bronze Supporter
Sep 3, 2018
1,129
Gilbert, AZ
Pool Size
17000
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
OK. I finally got a chance to do the fading endpoint test. My results are all over the place. So the first time I did it I got 21 drops + the first 5 so 26 drops = 650. It still turned purple so I did the distilled water test. I got 7 drops + the first 5 so 19 drops = 475. It still turned purple first. My initial test last week was 725. I did the distilled water one again and got 8 drops, so 21. That's a huge range! I like the 475 number but which one can I trust?
 
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mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
44,424
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
This is a new pool so the 475 ppm number makes sense. Means you have evaporated a complete pool volume since you filled it. About right for a summer in Phoenix.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
44,424
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
My pool in Laughlin will evaporate about 2 times pool volume each year. I believe Phoenix is a bit less. Do a search for Pan Evaporation Rates.

From Az Dept of Water Resources.
For example, in Phoenix and Tucson, the average evaporation rate is approximately six feet per year, most of which occurs in summer.
 
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Texas Splash

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Jun 22, 2014
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Texas, San Antonio/Marion, South-Central Area
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So when I test my CH should I always do the distilled water test?
You shouldn't have to. Once you get used to the test and how/when your fading end-point will occur, you shouldn't need it.

 
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Nikilyn

Bronze Supporter
Sep 3, 2018
1,129
Gilbert, AZ
Pool Size
17000
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Our pool is being drained for some plaster work. Since my picture shows that we have metals in our water, should I add a sequestering agent when we refill?