Total Alkalinity very high

[Ezz]

So recently bought a home in Scottsdale with a pool, never had a pool before. Pool looks great, clear water, pump runs fine with a barracuda vacuum about 8hrs per day. Decided to test the water out of curiosity. Chlorine level is good around 2.0, PH is good around 7.4. However total alkalinity is incredibly high - maybe 250ish ppm. Wondering how I can reduce the TA without throwing off my other measures? What are the concerns with high TA anyways?
Thanks!
Joe

 

[JamesW]

If those numbers are accurate, I would suspect that the cyanuric acid is probably super high.

What are the other readings?

What test kit do you have?

 

[Jimrahbe]

E,

Welcome to TFP... A great place to find the answers to all of your pool maintenance questions...

If you believe that a chlorine (FC) level of 2 is good, you really, really need to look at our pool school and this chart... Trouble Free Pool

As long as your CSI reading is between .3 and -.3 you should be ok... I would not adjust TA just to get to a number unless you need to do so to get your CSI in range.

It is really hard for us to provide advice when we only have half the data we need.. Below is the info the helps us determine the health of your pool water...

FC
CC
pH
TA
CH
CYA
Salt (if a saltwater pool)
Water temperature
CSI
Volume of pool (Normally in your signature, along with type of pool and equipment..)

Thanks,

Jim R.

 

[Ezz]

I have an HDX 5 way test kit. Those were the only 3 tests I ran

 

[Jimrahbe]

E,

The TFP pool care process is based on having an accurate test kit. If you think of us as "Pool Doctors" we need results that we can understand and compare, before we can determine just how sick your pool is...

We recommend either the TF-100 (what I have) or the Taylor K-2006C (and yes, the 'C' is important).

Thanks,

Jim R.

 

[Ezz]

Ok sounds like you are telling me the kit I have is garbage. Fair enough - I’ll order a better kit and repost with new results.
Thanks,
Joe

 

[duraleigh]

Good work! I wouldn't be surprised if your TA is not nearly as high as that first test indicates.....let us know

 

[rajung]

About your high TA, our city water is around 280ppm.
Always a hassle getting it down with MA in spring after partial refill.
Once you add MA and aerate, your numbers will change some during the process but all test numbers will fall into place

 

[JamesW]

If the fill water has a high TA, then the pool might have recently been drained and refilled.

Check the fill water TA.

 

[splashpad]

I have an HDX 5 way test kit. Those were the only 3 tests I ran

How old is your test kit? Can you run the full set of tests and post the results. Has the kit been stored in climate control?

Which test kit a pool owner owns/uses, still needs to be stored properly.

 

[cfherrman]

With high ta your pH is typically high. In my case 250 ta leads a dead set 8 pH untill you lower the ta.

 

[Ezz]

Ok all, got my TF100 kit and ran the tests.

FC 9
CC 0
PH 7.3
CH gave up after 50 drops color would not turn - not surprising as I believe we have the hardest water in the US here in Scottsdale
TA 270
Temp 65
I believe pool volume is around 12,000 gallons- hard to be sure it’s a jelly bean shape

Thanks,
Joe

 

[JamesW]

Is that from the pool or fill water?

Can you post both results?

What is the pool cyanuric acid level?

 

[mknauss]

You did use the 10 ml water sample for the CH test, correct?

Next time, try the following from the Test Kit Directions
add five drops of R-0012 before adding any R-0010 or R-0011L. Remember to count the initial five drops in the total.
In extreme cases, a fading endpoint may occur even when adding five drops of R-0012 at the start. If that happens, mix pool water with an equal quantity of distilled water, test that, and then multiply the result by two.
.

 

[Ezz]

Results above are for pool water. CYA must be very high as I only filled the tube about half an inch before the dot disappeared. Which is well below the first threshold of 100.
I can run the fill water later

 

[mknauss]

You need to run the extended test for CYA --
See Step 8 in CYA test directions.

 

[mknauss]

I would suspect you are going to end up doing a complete water exchange. So determine how you wish to do that. I have a procedure to do it without draining.

 

[JamesW]

The high CYA explains how the TA can be so high with a low pH. It's because most of the TA is cyanurate alkalinity instead of carbonate alkalinity.

In any case, you will probably need to do a significant dilution.

 

[Ezz]

So I reran the tests today for pool and fill water:

Pool
FC - 9
CC - 1
PH - 7.3
TA - 260
CH - went clear at 50 drops and after 90 drops was still not blue?
Temp - 65
CYA - did not hit bottom line, well over 100
CYA extended - did not hit bottom line, well over 100

Fill
FC - 0
CC - 0
PH - 7.8
TA - 100
CH - 375
CYA - 0

So it seems that despite the fact that the water is clear and causes no irritation to swimmers the chemical makeup of the water is a mess.

Looking for recommendations on ways to address - drain completely? Drain partially? Other?

Thanks again,
Joe

 

[cfherrman]

Yeah you need a complete drain and refill, you have to do it right.

Look at the tarp method or Marty's method