How to Address High pH and TA

[00xavier]

Hello Everyone, I just joined the forum this weekend. I purchased a TF-100 test kit and came back with the following results below. I have a Pebble Tec pool with a very strong southern exposure in Houston, Texas. My pool volume is 29,400. I need some help determining what my target numbers should be in PoolMath so that I can balance my chemicals properly. I would greatly appreciate any help you can give me.

I have been buying my chemicals from the pool store. I have been using 3" Pro Team Pool High Tech 3" Chlorine Tabs that have some borates. I would like to switch liquid chlorine and used concentrated Clorox. Do you recommend this?

What is the most cost effect way to lower my pH and Alkalinity?

Here are today's test results:

FC = 4.5
CC= 1
TA= 150
pH=8
CH=350
CYA=90
Borates=60-65

 

[svenpup]

Have you read through pool school? All your questions can be answered in the following links. Use muriatic acid to keep your pH in range and your TA will slowly come down over time. Your CYA is too high from all your use of pucks, so you probably wan't to drain about 1/3 and refill.

:lookhere: What is TFPC?
:lookhere: Recommended Pool Chemicals
:lookhere: How to Chlorinate Your Pool
:lookhere: Chlorine CYA Chart
:lookhere: Recommended Levels
:lookhere: PoolMath

 

[RobbieH]

I would like to switch liquid chlorine and used concentrated Clorox. Do you recommend this?

Hello, and welcome to Trouble Free Pool!

Yes, this is what we recommend!

The comments above are correct, use some MA to bring down pH to 7.2, how much to use can be calculated with PoolMath. TA will come down on its own.

 

[00xavier]

Thank you! How may I reduce the CYA without draining pool water? Should I add the MA all together or should I break it up over several days?

 

[Daltex]

Your CC of 1ppm means you have some "stuff" in your pool. I would SLAM it just to be sure. You can do this without lowering your CYA if you don't mind using monster amounts of bleach. Mine has dropped from around 90 to between 50 and 60 over time but if I had to do it all over again I would have drained some and lowered it from the start.

Get your pH to 7.2 range first- try adding about half a gallon of muratic acid. You can get it at Lowes here in Dallas but get it from where ever because it's not that expensive.

Your shock level will be 35 at your current CYA level so that would mean adding 11 jugs of 121oz. bleach @ 8.25%- ie. concentrated Chlorox

Once you finish the SLAM the your target range FC will be 7-12.

Since you stop using the tabs which are acidic, you will need to add acid manually more often so once you finish the SLAM and the FC drops below 10ppm retest pH and keep it within range.

 

[gwegan]

There are basically two ways to reduce CYA: drain and reverse osmosis. Draining is almost always less expensive.

Add the acid all at once then test the next day.

You are probably going to be having to add acid for the life of your pool. Your pool is less than a year old so you should figure on adding acid about twice a week for the next year. By then your pool should develop its personality chemically and its acid use should be more predictable. Because you have a negative edge you will however always have a rising ph. Water features that aerate the water create ions which raise ph.

 

[00xavier]

Do you think I need to drain 1/3 of the pool water to reduce CYA during this swim season or can I wait until October when the season is over?

 

[gwegan]

You can wait. BUT understand that you are going to be using much more chlorine to keep the free chlorine levels in a proper range.

You need to test for chlorine levels with a TF 100 or similar test kit every couple of days and add chlorine as needed. Use Pool Math above to determine what you need to add. Pool Math says your minimum FC should be 7 and can go up to 12.

 

[00xavier]

Thanks!