brendadmeyer

New member
Jul 23, 2022
2
Fulshear, TX
Pool Size
16000
Surface
Plaster
Chlorine
Liquid Chlorine
Hi, I have been doing my own testing for 4 months now and have some questions:

  • The Total Chlorine is all over the place (from 5 to 27 to 11.5)
  • the CH ppm has dropped to 275 after holding steady from 300-400
  • the TA is holding at about 100
  • the CYA has NEVER been as low as 40-50—but holds above 100
  • I used to put CL tabs (3-5 weekly) but haven’t put in any in the month of Nov.
  • the PH is holding at 7.2-7.5

The daily pH and Chlorine test (I do weekly)—started showing orange color on the yellow side—hence I stopped adding chlorine tabs.

  • I’m attaching my pool chemicals spreadsheet—and want to know if I’m doing this correctly or what?
  • Should I add chlorine again or wait until the daily test shows yellow again?
 

Attachments

  • 12-1-22PoolChemicalsSS.pdf
    71.2 KB · Views: 3
B,

Your main problem is that you CYA is above 100 and since the test kind of tops out at 100, there is no telling what your actual CYA level is.

There is no fix for high CYA except to drain and refill your pool.

Anything else you do is almost a waste of time.

Thanks,

Jim R.
 
B,

Your main problem is that you CYA is above 100 and since the test kind of tops out at 100, there is no telling what your actual CYA level is.

There is no fix for high CYA except to drain and refill your pool.

Anything else you do is almost a waste of time.

Thanks,

Jim R.
Thanks--I think it is running at 110-115. Do I still need to drain and refill?? YIKES!
 
Hey! Welcome to TFP! :swim:

I would perform a diluted CYA test as follows:
Add pool water to bottom of sticker/bottom line.
Add tap water to top of sticker/bottom line.
Shake.
Pour out half so mixture is to bottom of sticker/bottom line.
Add reagent to top of sticker.
Shake.
Test outside with back to sun and tube at waist level.
Pour back and forth a few times to see if you get the same result.
Double the result.


Doing this will give us a more accurate picture of your ACTUAL CYA. With that we can tell you how much to drain/replace.

I would also read this, three times. I highly recommend doing the no drain exchange.
 
The Total Chlorine is all over the place (from 5 to 27 to 11.5)
Your recent testing shows you had FC at 11 and added 3 pucks. Then it rose to 18, then to 16, then to 30 and back down to 11. I live fairly close near you and the weather has not effective that much i.e. strong UV or cloudiest. I would check your test procedure and ensure your reagents are not expired. I can see the decline in the most recent test due to our rain and then sunshine but interesting that 3 pucks raised to 30. 3 pucks of trichlor if all fully dissolved instantly would only raise your FC by 10ppm, but these are slow release so I don't understand the significant increase to 30 then immediately back to 11.

the CH ppm has dropped to 275 after holding steady from 300-400
Dilution due to rain or if you backwash and replace water can lower your CH. CH is like CYA, it stays in the water unless you drain. Each drop is 25ppm (10ml sample) so you can be off by 1 drop either way.

the CYA has NEVER been as low as 40-50—but holds above 100
As Jim indicated, you may be significantly above 100 - the scale is logarithmic so you cannot guess. Have you tried the dilution method? The use of pucks will continue to raise CYA. the 3 pucks recently added will raise CYA by 6ppm. CYA does not go away unless you physically remove water by draining.

the PH is holding at 7.2-7.5
I am surprised this is holding since you have not added pucks, which contain Acid - the 3 pucks you added would lower pH by 0.6 when fully dissolved. I would expect it to start to rise since your TA is at 100.
 
Brenda, I'll try to explain why you may be having problems.

-Using pucks causes the CYA which is an ingredient in the puck to build up. So your CYA level gets out of hand and you don't realize it until a problem develops.
-Too much CYA requires higher Free Chlorine (FC) to keep the pool clean and sanitized. So we don't want too much or too little CYA.
-Pucks also are acidic so they tend to keep your pH down.
-Your TA (total Alkalinity) role is to act on your pH- so a high TA will "pull up" your pH, and a low TA will allow the pH to remain lower.
-Your pH along with other chemistry elements combine to give you a CSI (Calcium Saturation Index) which goes a FAR way in protecting plaster and equipment from damage. So if you're having problems its time to learn about all aspects of your chemistry and learn what balance for your pool entails.
-Liquid Chlorine or a Salt Water Chlorinator are better options for sanitation. Neither one adds unwanted extra ingredients to the pool water.

Please ask away anything that confuses you-

Maddie 🇮🇹
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.