Frustrated

[Rohr]

Guys,
Just had new liner installed and refilled pool 13500 gals. switched to SWG in the process. Have not started the SWG because I cannot get my PH and TA in range. TA 195-200 PH 8.2-8.4. I have added one gallon of Muriatic acid 31.45%. in the last four days with no change had a few dips but always comes back up. I know this question has been asked a thousand times and I feel like I am doing what I need to do. Any help is appreciated. BTW salt level is 3500.
Thanks

 

[Bama Rambler]

Welcome to TFP.

It may take a lot of acid to get the TA and pH where it needs to be.
What test kit are you using?
If you're using the K-1000 for pH, it may be higher than 8.4.

What is the TA and pH of your fill water?

 

[Texas Splash]

Hello and welcome to TFP! Our first question might be .. What are you testing with? Is it a TF-100 or Taylor K-2006? If not, that may be something you want to consider first. If you are using one of those kits, then it's just a matter of consistency and applying the amount of acid required to lower pH enough as outlined on the Pool School - Lower Total Alkalinity page to make productive gains. Also make sure you're using the Poolmath Calculator as needed to confirm the right amount of acid for each application. (link below). Have a nice day.

 

[pabeader]

When pH is near the extremes of the tester, it is possible to be over the limit. So in your case it may be more then 8.4 and may take a few applications to get it down where you want it. Just dose, wait a while with the pump running, retest and dose as needed. It will eventually stay down. Don't forget, a high TA will drive the pH up as will any kind of aeration like spillovers and fountains.

 

[Richard320]

Welcome

Playing with poolmath, I see it taking about 76 ounces of 31.45% acid to lower pH to 7.2. That's over half a gallon. Scrolling down to Effects of Adding Chemicals, it says 76 ounces of acid will lower TA by 22. So, roughly 10 TA per quart of acid, or 40 per gallon. If you want to reduce TA by 120, it's going to take 3 gallons of acid. If you're buying the half-strength stuff somewhere, six gallons. That's just what it's going to take, period. You can't change the laws of chemistry. DON'T add the three gallons all at once! The process is to lower pH to 7.2 using whatever dose of acid poolmath calculates. It will take less and less each time as the TA lowers. Then you aerate to raise pH. Then you dose it again with acid. Repeat until TA is down in range. When it is, pH will stay stable for several days at a time, perhaps even weeks once you find your pool's sweet spot.

To aerate, aim the return up so you get ripples on the surface. Many people have devised fountains and jets using PVC pipe. I've seen submersible pumps connected to a lawn sprinkler, even someone who just hooked a hose to a ladder so it would hit the pool from a few feet up to break the surface. Even a couple rowdy kids having a splash fight will aerate a lot. If you use the search box for things like homemade aerator or PVC fountain, you'll get some ideas.

Here's the process explained in more detail Pool School - Lower Total Alkalinity

 

[Rohr]

Thanks for all the information. I have better readings this evening 7.4 and 100. Not sure if it came down because of the additional time and 16 oz. of muriatic acid or the downpours we have had for the last day. I do not think I have a good test kit. I have been using a combination of three and checking each one against the other. A HTH 5 way test kit, Aqua check digital meter that uses test strips and a Aqua Chem test kit. I have read the suggestions on this site for test kits and wanted to know what you guys think?
Thanks again for all the help

 

[Texas Splash]

I would recommend the TF-100 with Speed Stir (link below). Best thing I EVER bought for my pool. It has paid for itself MANY times over in wasted chemicals and effort.