Balancing after No Drain Acid Wash?

[Apuri]

This is my first year as a pool owner, the pool itself being about 8 years old. I read through this forum and am learning the BBB method and have recently purchased the K2006 testing kit as well.

I just recently cleaned up the calcium scale in my pool by adding 4 gallons of muriatic acid. 48 hours later the scale is gone but as expected the alkalinity and pH are too low to register on the testing kit. Even the Dpd test is not turning the water pink so chlorine levels are very low too.

Can some one please help in the sequence and how much of BBB to add at a time to bring the chemicals back to balance. I read somewhere that the alkalinity needs to be brought up slowly, only so much of baking soda to be added every 3-4 days, run/not to run the pump just after adding baking soda etc. I need some guidance here.

I have a 10,000 gallon concrete pool.

Thanks.

 

[Patrick_B]

Welcome to the forum Apuri!

We sure can, but if you will post up a full set of numbers from your 2006, it would give us a much better place to start. Do that, and you'll get plenty of replies before you know it.

Your pH sounds critically low, so do you have some Borax to raise it? If not, you'll need to get some. Also, Does your TA not turn green at all when you prepare the sample?

 

[Apuri]

TA doesn't turn green at all. I do have a box of Borax (I think 4 pounds) on hand.

I will get a complete set of readings shortly.

So far,
TA: already pink when I add R0008
Dpd test: do not turn pink
PH: light yellow color

Welcome to the forum Apuri!

We sure can, but if you will post up a full set of numbers from your 2006, it would give us a much better place to start. Do that, and you'll get plenty of replies before you know it.

Your pH sounds critically low, so do you have some Borax to raise it? If not, you'll need to get some. Also, Does your TA not turn green at all when you prepare the sample?

 

[Patrick_B]

Ok, normally we are worried about FC first, but you are very low on pH and that needs correction immediately. Im about to be offline, but hang tight for just a bit.

 

[Richard320]

Welcome!

My opinion, and worth every penny you paid for it is this:
1) add enough baking soda to get TA to 60 or 70. Poolmath says roughly ten pounds to get there from zero. But you should plug in your current TA reading before you just start dumping. This is a good tutorial on using poolmath. The reason for raising TA first is because it acts as a buffer - a shock absorber - when you make pH adjustments. As your water is now, an ounce or two off either way with the pH adjuster and your pH can still be way off.
2) Brush that baking soda around to mix it well. Then check pH. The K2006 Base Demand might be necessary. If the pH is below the scale, it could be 6.8 or it could be 2.0 - you just don't know. The Base Demand test will help you get in the ballpark. Use Washing Soda or Borax to raise the pH. If you already have some soda ash from the pool store, use it. But if you need to buy something, head for the grocery store. See Recommended Pool Chemicals.
3) After pH has had half an hour or so to stabilize - and again, brushing helps mix things better than just plain filtering - add enough bleach to get to the target for your CYA.
4) Give things a few hours to stabilize, and then recheck it all and fine tune it. Don't expect to get things dialed-in 100% immediately. It will probably take a little bit of back-and-forth. It's easy to fix low TA or low pH by just adding more chemicals. If you overshoot, it can cause problems. Aim low and then come back and finish.
5) If, by chance, you have high CYA or super-high Calcium after the treatment, now is the time to do a partial drain. But I'd still get the pH and TA close before I used my filter pump to empty it, because acidic water can damage the metal in the heater. If you have a sump pump and you need to replace some water, use that.

 

[Apuri]

Here are the readings:
FC - does not turn pink when I added DPD
PH - light yellow color
TA - already pink when I add R008
CH 300
CYA 30

I have 12lb baking soda, 4lb borax and about 3 gallons of bleach on hand.

 

[Richard320]

Here are the readings:
FC - does not turn pink when I added DPD
PH - light yellow color
TA - already pink when I add R008
CH 300
CYA 30

I have 12lb baking soda, 4lb borax and about 3 gallons of bleach on hand.

You're doing good! Have at it. http://www.troublefreepool.com/content/139-recommended-pool-chemicals will tell you the best way to add each chemical.

 

[Apuri]

Welcome!

My opinion, and worth every penny you paid for it is this:
1) add enough baking soda to get to 60 or 70. Poolmath says roughly ten pounds to get there from zero. But you should plug in your current TA reading before you just start dumping. This is a good tutorial on using poolmath. The reason for raising TA first is because it acts as a buffer - a shock absorber - when you make pH adjustments. As your water is now, an ounce or two off either way with the pH adjuster and your pH can still be way off.
2) Brush that baking soda around to mix it well. Then check pH. The K2006 Base Demand might be necessary. If the pH is below the scale, it could be 6.8 or it could be 2.0 - you just don't know. The Base Demand test will help you get in the ballpark. Use Washing Soda or Borax to raise the pH. If you already have some soda ash from the pool store, use it. But if you need to buy something, head for the grocery store. See Recommended Pool Chemicals.
3) After pH has had half an hour or so to stabilize - and again, brushing helps mix things better than just plain filtering - add enough bleach to get to the target for your CYA.
4) Give things a few hours to stabilize, and then recheck it all and fine tune it. Don't expect to get things dialed-in 100% immediately. It will probably take a little bit of back-and-forth. It's easy to fix low TA or low pH by just adding more chemicals. If you overshoot, it can cause problems. Aim low and then come back and finish.
5) If, by chance, you have high CYA or super-high Calcium after the treatment, now is the time to do a partial drain. But I'd still get the pH and TA close before I used my filter pump to empty it, because acidic water can damage the metal in the heater. If you have a sump pump and you need to replace some water, use that.

Thanks Richard. I just did the base demand test. It took 12 drops to bring the pH to 7.0. Hope this helps.

Question? Can I add the 10 lbs of baking soda in one go? or need to do it in intervals? Also, should the pump be running at all times during this process?

 

[Apuri]

Ok, normally we are worried about FC first, but you are very low on pH and that needs correction immediately. Im about to be offline, but hang tight for just a bit.

Patrick, any word of advise?
So far I have added 2 lbs of baking soda and 1 cup of Borax. Reading through online posts, some folks had issues adding a lot of baking soda too fast, so quite hesitant and looking for some guidance. Thanks.

- - - Updated - - -

Also, at what stage do I start adding Bleach? And how much?

 

[Divin Dave]

Hi Apuri,
Run the pump at all times when adding stuff, and least an hour afterwards you can swim
You can test for your levels after they have mixed in for 30 minutes (except for CYA, that takes several days to register).

I would recommend adding only half of the baking soda for now so you dont overshoot. ..then wait 30 and test.

Do you know how to use Pool Math yet? Its very handy.
At top left, enter your pool volume.
In the now column, add your level when testing
In the target column, enter what you want to raise the level to.
Then click the calculate button, and pool math will tell you how much of something to add in order to reach your target.
http://www.troublefreepool.com/calc.html

and here is the recommended levels chart in case you havent found it yet.
http://www.troublefreepool.com/content/134-recommended-levels

When you have your TA and ph up a bit, then add bleach. The FC level depends on what your CYA is. Here is the FC/CYA chart.
http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

 

[Apuri]

Thanks. I will add another 5 lbs baking soda and test after 30 mins. How about Borax? Do I add now and start raising pH or wait till TA gets more in line?

I am looking at pool math now... Pretty handy tool.

Hi Apuri,
Run the pump at all times when adding stuff, and least an hour afterwards you can swim
You can test for your levels after they have mixed in for 30 minutes (except for CYA, that takes several days to register).

I would recommend adding only half of the baking soda for now so you dont overshoot. ..then wait 30 and test.

Do you know how to use Pool Math yet? Its very handy.
At top left, enter your pool volume.
In the now column, add your level when testing
In the target column, enter what you want to raise the level to.
Then click the calculate button, and pool math will tell you how much of something to add in order to reach your target.
http://www.troublefreepool.com/calc.html

and here is the recommended levels chart in case you havent found it yet.
http://www.troublefreepool.com/content/134-recommended-levels

When you have your TA and ph up a bit, then add bleach. The FC level depends on what your CYA is. Here is the FC/CYA chart.
http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

 

[Divin Dave]

Wait till after you add the Baking Soda...then check the Ph again. Then add borax if you need to.

One other note about adding stuff, only add 1 thing at a time, never mix different chemicals in together.

Man, I dont know what we would all do without Pool Math. Its a life saver for sure!

 

[Patrick_B]

Let's get this pH in line before anything else today. You ought to be closer to normal now, but let's see. Sorry I haven't been back, but it's been really busy here today.

 

[Divin Dave]

Wait till after you add the Baking Soda...then check the Ph again. Then post up what your TA and Ph level tests say.

as a note, If you look at the bottom of pool math, there is a section called THE EFFECTS OF ADDING... you can use that to determine how one thing effects another.

 

[Apuri]

Just tested. TA is now at 40ppm; pH still very low (had to add 4 drops of base test to register 7.0).

Since TA is increasing by adding baking soda but not pH, at what stage should I start using Borax (i think both pH and TA increases, correct)?

Wait till after you add the Baking Soda...then check the Ph again. Then post up what your TA and Ph level tests say.

as a note, If you look at the bottom of pool math, there is a section called THE EFFECTS OF ADDING... you can use that to determine how one thing effects another.

 

[Patrick_B]

Ok, does your pH get close to 6.8 or 7.0 on the color block test?

Answer that, but let's get the TA up to about 70 then see where pH is. Better to miss and hit 65 TA than 75-80. Add /measure carefully. You can always adjust up a little if needed.

 

[Richard320]

Just tested. TA is now at 40ppm; pH still very low (had to add 4 drops of base test to register 7.0).

Since TA is increasing by adding baking soda but not pH, at what stage should I start using Borax (i think both pH and TA increases, correct)?

Simple rule: Baking Soda raises TA a lot and pH a little. Borax raises pH a lot and TA a little.

You're making progress. I'd keep going on the Baking Soda, since it does seem to be pushing pH upwards as the base demand is going down. You don't want the two chemicals to gang up and push pH too high, because then you'll just be adding acid to lower it. That sort of yo-yo effect is the pool store method.

 

[Apuri]

it was still yellowish. I added 1 drop at a time for the base test and got to 7.0 (lowest color block on k2006) after 4 drops.

Ok, does your pH get close to 6.8 or 7.0 on the color block test?

Answer that, but let's get the TA up to about 70 then see where pH is. Better to miss and hit 65 TA than 75-80. Add /measure carefully. You can always adjust up a little if needed.

- - - Updated - - -

Yes, I will aim to get TA to 70 in the next hour or so. And then move to Borax to fix the remaining pH. I promise I will be in constant touch

Simple rule: Baking Soda raises TA a lot and pH a little. Borax raises pH a lot and TA a little.

You're making progress. I'd keep going on the Baking Soda, since it does seem to be pushing pH upwards as the base demand is going down. You don't want the two chemicals to gang up and push pH too high, because then you'll just be adding acid to lower it. That sort of yo-yo effect is the pool store method.

 

[Divin Dave]

You're doing good man,
Keep up the good work!

 

[Apuri]

Ha! Thanks to help from all of you.

Ok. So finally I got to TA of 70ppm, pH is still low, 2 base test drops to get to 7.0

So I am guessing next round will be about 2 lbs of Borax (7.0 to 7.4 pH per Pool Math)... and then end the day with about 60 oz of 8.25% bleach (0 to 4 TC as per Pool Math).

Does that sound about right?

You're doing good man,
Keep up the good work!