Need an Alternative Way to Test CH

[Triumph65]

I have read the thread in link below about testing CH and getting red clumps that make the test unreadable.

CH Test - reagents not mixing

I figured this would best be a separate thread than my FC thread. Both times today that I've tried totes my CH, the reagents have failed to mix properly with the water. The colored reagents, as shown, are "clotting" in the water. This doesn't seem to be normal behavior and I'm starting to think...

www.troublefreepool.com

Have tried all the suggestions from Taylor to no avail.

I’ve tried both Taylor and TFT kits with fresh reagents and nothing works. Must be too much magnesium the water.

@JoyfulNoise suggested diluting with distilled. I will try that next.

Question is this, I know some of the Aquarium reefers have CH testers they us. Might any of these work for pool water? Example below.

Hanna Instruments HI758 Marine Calcium Checker Test Kit - Saltwater Aquariums Amazon.com: Hanna Instruments HI758 Marine Calcium Checker Test Kit - Saltwater Aquariums : Pet Supplies

Thanks!

 

[ajw22]

Let's see what @JoyfulNoise has to say about the marine calcium checker.

 

[JoyfulNoise]

Email Hanna. My guess is it won’t work right for pool water that is chlorinated. Chlorine affects a lot of dye reagents. Also check with them on magnesium interference.

 

[JamesW]

Maybe use some thiosulfate to neutralize the chlorine.

Does the water contain copper?

Do you have any idea what the approximate calcium hardness is?

Does the test work correctly on your tap water?

 

[Triumph65]

@JamesW - My tap water still comes from the well and also has high enough levels of magnesium to make the red globs in the CH test. I’ve tried all the methods listed in the linked thread, suggested by Taylor.

I did not fill this massive pool with my well, rather had the water trucked in. But that water source was apparently close enough to have the same magnesium.

The water may also contain copper but I have never tested for it.

It’s very frustrating but I can only approximate that the CH is above 200 using CH test strips. The problem is, the strips are very hard to distinguish above 250, the next color is 400. I tried that because tje Taylor and TFT tests are impossible to interpret with all the red globs.

 

[JamesW]

Do a 50% dilution with distilled water and then try the test with the modified test.

 

[JoyfulNoise]

I would suggest you *invest* the money in having a detailed water analysis done on your well water by a third party independent testing lab. Have them check all possible metal levels, not just the “basic” water test. You should even look at organic contaminants. Radionuclide testing is not necessary. Well water can be very tricky to deal with sometimes and Texas can have quite the variation in water quality. If the well is contaminated with something that is possibly dangerous or unhealthy, then it’s best to know that’s now. I’m not saying it is, but it’s clearly not reacting to standard test chemicals appropriately.

 

[Triumph65]

@JoyfulNoise - That is a good idea and I will find out where I can have a water sample tested in central texas. Sorry I missed this last comment for a couple weeks.

 

[Triumph65]

Maybe use some thiosulfate to neutralize the chlorine.

Does the water contain copper?

Do you have any idea what the approximate calcium hardness is?

Does the test work correctly on your tap water?

@JamesW -
Thank you for your suggestions. It has been a busy week and I am still working this issue. On a side note I did call Hanna and got their 200-600ppm Hardness photometer. They stated that they have customers that also use them
for pools, so I decided to give it a try. I tested my RO filtered softened water, tap softened water and pool water. All read 200ppm which is below the measurement scale - meaning they are all sub <200. My son was happy to relieve me of the Hanna H1758 to use for his reef aquarium. He tested his reef water and the results agree with his titration test.
I may try some thiosulfate to neutralize chlorine and try the Hanna again. I will also do the same with the Taylor and TFT CH tests to see if that helps.
I called my pool technician for help as well, as he owns a spin touch. I would never trust the spin touch over Taylor/TFT testing but without a way to accurately test for CH, I was desperate.

I have attached results for his testing for:
1. Well water
2. Current pool water
3. Pool water in February of this year.

Will also send my well water away as @JoyfulNoise suggested. I did not fill the pool with my well water, only have been using for top off. The top off is considerable however as it’s usually hot, windy and dry. I lose a good bit to evaporation.

The calcium numbers for the well, pool present and pool past are all in the spin touch photos, including copper.

Per your last question. My tap water is softened so not sure if that would effect the test or not but I will give it a try. I tried the CH test on softened tap water jut to see what would happen and it immediately turned dark blue, when adding R0011.

Sorry for long post. Appreciate your help.

 

[Triumph65]

On a side note. I have not been using the speed stir recently but did so yesterday, after reading JoyfulNoise’s suggestion previous post. This made the color change in reagent MUCH easier to see, as the twirling magnet broke up clumps. My result from that test was 375

 

[arvil]

Yeah, love that speedster, I use for my aquarium testing as well. My aquarium testing chems says that I need to shake well the reagents as they may settle, that may make a difference. I use the TFT CH test on my aquarium, but, if you like, the aquarium testing companies like API, and so forth have CH test. Maybe your son can run the test with his test kit. May need to add a couple of drops R7 to neutralize chlorine.

 

[Triumph65]

but, if you like, the aquarium testing companies like API, and so forth have CH test. Maybe your son can run the test with his test kit. May need to add a couple of drops R7 to neutralize chlorine.

@arvil - He tried his titration kit last night but we did not neutralize chlorine. We will try again tonight and do that. May try the Hanna again as well with some R7.

Using the Speed Stir neutralized most of the big red globs and made the change from red to blue discernible. My results of 375 differ from my pool techs spin touch. I only had him test because he was over working on my equipment and I’ve been having problems testing and with scaling on tiles (white at waterline).

I’ve been really struggling with high TA and rising PH. It is probably due to my well fill water. Now using softener for fill water so that should help