Rookie CH concerns

Jump to latest Follow Reply
S

slperrine1

Member
Aug 13, 2024
12
Charleston, SC
Pool rookie in need of guidance, especially in regard to my CH dropping down to O after fresh water deluge from hurricane Debby. CH tested at 110 on 8/13, then dropped to 0 by 8/18. Pool Math recommended addition of 23 lbs of Calcium to get back up, which I have done but am still testing at 0 for CH two days later, using a Taylor K-2006C Salt test kit. Expiry dates on test kit are all 2025 and other tests from kit seem to be accurate. Would greatly appreciate guidance on raising CH. Worried about negative effects of no/low Calcium. Have been enjoying all Pool School articles and forums on TFP, as well as Pool Math. Was feeling pretty confident about doing this on my own. Now feeling a bit panicky, honestly. Thanks in advance for your support!

Pool size: 8,380
Location: South Carolina
Surface: Plaster
Chlorine: Salt Water Generator
SWG Type: Hayward TCELL S340X25

Test Results for 8/20:
pH: 7.8
FC: 8.4
CC: 0.8
TC: 8.6
TA: 80
CYA: 60
CH: 0
Salt: 3200
 
Welcome to TFP!

Something's wrong, you'd have to have had 100% of your water replaced with rain water for that to happen. If that had happened your CYA and salt would have also dropped to zero. And 23 pounds would have raised your CH by 300 ppm, so everything is pointing to testing error.

Can you describe, step by step, how you are testing? I know it might feel a bit insulting being asked, but we've all mixed something up from time to time and that's the number one most likely answer here.

EDIT: Oh, and no need to panic. There's very little chance your CH is actually zero.
 
Last edited:
  • Like
Reactions: JoyfulNoise
Donldson said:
Welcome to TFP!

Something's wrong, you'd have to have had 100% of your water replaced with rain water for that to happen. If that had happened your CYA and salt would have also dropped to zero. And 23 pounds would have raised your CH by 300 ppm, so everything is pointing to testing error.

Can you describe, step by step, how you are testing? I know it might feel a bit insulting being asked, but we've all mixed something up from time to time and that's the number one most likely answer here.

EDIT: Oh, and no need to panic. There's very little chance your CH is actually zero.
Click to expand...
Thanks for your speedy (and gracious) reply! Yes, given I’m the only one doing the testing there’s certainly a possibility for user error. I am following the Taylor test kit instructions for CH. I fill the large tube to the 25mL mark with sample water, then add 20 drops of R-0010 and swirl to mix. Then add 5 drops R-0011L. Swirl to mix. Then the instructions state, “If calcium hardness is present, sample will turn red.” Here’s where I’m stumped. That sample is clear, not red.

Interesting. Now that I’ve spelled all that out, I’m wondering if I miscalculated the drops of R-001L. Great suggestion to have me go through the steps again, thank you. I’ve got to get to work, but when I get home I’ll slow down and test again, very carefully, and update. Thanks again for your support and reassurance. Have a great day!
 
Wow - that's a lot of drops! My TFTest Kit says to fill the cylinder to 10ml, add 10 drops of R-0010 and then 3 drops of R-0011L. It does not turn the water a deep red but it is not clear.

Maybe try the TFT quantities and see if it turns blue after XX drops of adding R-0012 (Multiply the # of drops by 25 to get the calcium PPM).
 
When you get the chance to do it again, continue the test even if the test doesn't turn red. The test isn't complete until the sample is as blue as it can get, so add the r-0012 and see if you can get it to a blue color. If it turns blue, continue adding drops until it stops turning more blue (if the final drop doesn't change the color further, ignore it in your final tally).

Sounds like something might be causing the color to not fully turn red, but since the sample isn't blue that's highly indicative that your water does indeed have calcium in it.
 
  • Like
Reactions: InyoRich
If you add R-0011L the water sample shoikd not be clear. It should either be red/purple (calcium is present) or blue (very low Ca present). A clear water sample would indicate that there is problem with the indicator dye.

Check your reagents. The R-0011L has a limited shelf life and can go bad easily where it clumps up in the bottom. Make sure you are using the right reagents and not accidentally grabbing the wrong bottles. Believe it or not, people add the wrong reagents all the time.
 
Much appreciate the suggestions. Interesting results, although maybe a bit disappointing in that I’m still not clear what the user error was. Donldson, your instincts were spot on: definitely user error and, yes, no chance my CH was really zero. Quite the contrary, actually. See test results below.

InyoRich, I appreciate the suggestion to test with a smaller sample (10mL). I found it easier to read/evaluate because the color was more saturated.

I began retesting by carefully inventorying and organizing my test kit — just in case I had things mixed up.

I conducted four tests total — two of the 25mL sample test and two of the 10mL sample test. Results were:

25mL sample tests resulted in CH of 480. Test repeated twice with same results.

10mL sample tests resulted in CH of 450. Test repeated twice with same results.

So now I have NEW problem. High CH. TFP suggests CH range of 200-400. What are my next steps, please? I do not want to empty water from the pool. Can I adjust the pH to address the extra calcium?

Thank you all again for your wisdom and support.

As a reminder, other test results are:
pH: 7.8
FC: 8.4
CC: 0.8
TC: 8.6
TA: 80
CYA: 60
Salt: 3200
 
Are you having any scale? Does your SWCG shed scale?
Use CSI from PoolMath. Keep it between -0.3 and 0.

Your CH is not all that high.
 
You must log in or register to reply here.
Top Bottom
Back
Jump to latest Follow Reply