Low ph and high alkalinity at SWG pool start up

[SixOwls]

Hello. I am new to the forum but have been a pool owner for many years. I have my vinyl liner pool cleared up after my first major battle with ammonia and am ready to proceed with opening the pool. This year, I have installed a SWG also but haven't added salt or turned it on yet yet since I wanted to slam pool first and start with pool clean. My TF100 test kit is showing low pH off the scale (guessing 6.9?) when the TA is at 90, cya at 30, and FC is below 10ppm. I think the pH is so low because of the ammonia battle. I have been trying to aerate for over 24 hours (first time I have tried it) but no real change seen so far on pH and I want to move forward. A few questions: Wondering if I need to lower the TA with muratic acid and try to raise ph with borax OR would it would hurt anything if added the salt and just started up SWG knowing it will raise the ph on its own? Also - When is the best time to raise the cya to recommended levels for salt pool and when would be best time to add boric acid (trying that for first time also). I will note also that the pool store is measuring a higher pH of 7.2 and higher alkalinity of 110 even when the pH is down at 5 ppm, not sure why the differences. Thanks!

 

[ajw22]

Welcome to TFP.

Hello. I am new to the forum but have been a pool owner for many years. I have my vinyl liner pool cleared up after my first major battle with ammonia and am ready to proceed with opening the pool. This year, I have installed a SWG also but haven't added salt or turned it on yet yet since I wanted to slam pool first and start with pool clean.

You have a lot of moving parts.

My TF100 test kit is showing low pH off the scale (guessing 6.9?) when the TA is at 90, cya at 30, and FC is below 10ppm. I think the pH is so low because of the ammonia battle. I have been trying to aerate for over 24 hours (first time I have tried it) but no real change seen so far on pH and I want to move forward. A few questions: Wondering if I need to lower the TA with muratic acid and try to raise ph with borax OR would it would hurt anything if added the salt and just started up SWG knowing it will raise the ph on its own?

Raise your pH with a bit of borax and don't worry about your TA right now. Your TA is going to change with the addition of the CYA anyway.

Adjust your TA after all other chemicals are within range.

Also - When is the best time to raise the cya to recommended levels for salt pool

Do the SLAM Process at CYA 30 and after the SLAM is complete you can get CYA dissolving for CYA 60.

and when would be best time to add boric acid (trying that for first time also).

Later, way later, like next year.

Get your water chemistry stable including your TA. You have a lot of other things to do. Boric acid will only make TA adjustments more difficult.

I will note also that the pool store is measuring a higher pH of 7.2 and higher alkalinity of 110 even when the pH is down at 5 ppm, not sure why the differences. Thanks!

ph down at 5 ppm????

What are you using to test your pH?

How old are your reagents?

 

[SixOwls]

Thanks everyone! I am using the TF100 test kit and I just received it 2 weeks ago. PH bottle expires 3/25. Pool store was doing a drop testing method but not sure of specifics there. I mistyped before...I meant to say "I will note also that the pool store is measuring a higher pH of 7.2 and higher alkalinity of 110 even when the FC is down at 5ppm".

 

[SixOwls]

At what point in the process can I add the salt and get the generator going? Can I do that right away or do I need to get the balance all correct first. I am eager to not be pouring in chlorine or adding tabs after lots of slamming!

 

[ajw22]

You can get the SWG going once the SLAM process is complete meeting the 3 exit criteria.

 

[woodyp]

Add the salt and circulate 24 hours before kicking in the SWG.

 

[SixOwls]

Later, way later, like next year.

Get your water chemistry stable including your TA. You have a lot of other things to do. Boric acid will only make TA adjustments more difficult.

Ok. How do I know when everything is stable enough? If TA and pH come into limits and seem to be holding there, is there a certain amount of time that I need to wait before adding boric acid or why would it take until next year?

 

[ajw22]

Ok. How do I know when everything is stable enough? If TA and pH come into limits and seem to be holding there, is there a certain amount of time that I need to wait before adding boric acid or why would it take until next year?

When your TA Is low - 50 to 70 - and your pH rise is predictable and you can guess your likely pH and TA before even testing.