Water Chemistry - Whaddya Think?

Apr 11, 2010
14
Greetings,

My pool water is crystal clear. I have the following:
FC 3-5
pH 7.2
TA 230
CH 150
CYA 50

Should I be concerned about the high TA and/or low CH?

Thanks!
Mark
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,471
SW Indiana
You should be concerned about the low CH for the sake of your plaster.

If you just maintain your pH in the lower end of the range, TA will drop over time.
 
Apr 11, 2010
14
Thanks for the super fast replies!

I should have noted that I have been lowering the pH. It was 7.8. M

I haven't added any liquid chlorine in several days as I have been trying to bring down the pH and didn't want to add both chemicals on the same day. I tested with my new TF-100 kit. I used the FAS-DPD test for FC.
 

Butterfly

TFP Expert
LifeTime Supporter
May 30, 2007
10,045
South Carolina
ReluctantPoolBoy said:
I haven't added any liquid chlorine in several days as I have been trying to bring down the pH and didn't want to add both chemicals on the same day.
There is NO problem adding both chems on the same day, just make sure to have about 30 minutes pump time in between.

I suggest you add chlorine each evening up to your target level.

That is what most of us "Jug Dumpers" do :wink: (thanks for that svenpup :lol: )
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,397
San Dimas, CA (LA County)
ReluctantPoolBoy said:
Greetings,

My pool water is crystal clear. I have the following:
FC 3-5
pH 7.2
TA 230
CH 150
CYA 50

Should I be concerned about the high TA and/or low CH?

Thanks!
Mark
I find the CH number hard to believe, since you're in California. My tap water runs almost 300 CH! You didn't transpose the TA and CH numbers by chance?
 
Apr 11, 2010
14
Richard320 said:
I find the CH number hard to believe, since you're in California. My tap water runs almost 300 CH! You didn't transpose the TA and CH numbers by chance?
I tested it twice for the same reason! :)
 
Apr 11, 2010
14
Greetings!

I have been maintaining my target FC and a slightly lower than target pH. Just as John T. said, my TA is slowly dropping. It's now 180. Unfortunately, my CH is also dropping. It's now down to 100. I'm concerned about the low CH number. Is it time to add some calcium chloride?

TEST 4/11 6/27
------------------
FC 7 7
TC 7 7
pH 7.2 7.2
TA 230 180
CH 150 100
CYA 50 60
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
CH doesn't just drop like that, so I suspect there is a testing error of some kind.

For a plaster pool, you should keep CH between 250 and 350, so you definitely need some calcium even if your CH level is still 150.
 

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