First Timer with BBB method - order of operations?

[jreiser]

Hey folks,

First let me say thanks for this great forum. My wife and I are renting a house that has an inground vinyl pool which hasn't been open for a season or two, so we had our work cut out turning it from green (or black) to blue. Today is the first day that I'm seeing a nice blue/green in the shallow end, so we're definitely getting there after just about a week's work.

I've been keeping the pool in shock on a daily basis with 6% bleach and cleaning every day or two, backwashing a few times a day, and now I think I need to address the chemistry a bit more closely. Stats from this afternoon:
FC=7
CC=0.5
TC=7.5
pH=7.2
ALK=50
Stabilizer<20 (probably zero or close to it)

Following those meaurements, I added two 182 Oz containers of 6% bleach (just shy of 3 gallons) which should raise FC to ~ 12.5 per the Pool Calculator. I'll test FC again in a few hours and add some more if it has dropped below about 10.

The chlorine bleach seems to be doing a great job of removing the green algae from solution and depositing dead gray algae on the bottom and in the filter sand. So little by little we're getting somewhere.

I'm going to pick up some borax, baking soda, and Cyanuric Acid (CYA) to address the pH, Alkalinity and Stabilizer. Is it important to do these in any particular order? I know my CYA levels being zero is allowing chlorine to be burned off more easily by the sun, but surprisingly it hasn't been that extreme... perhaps because I'm staying on top of it.

I was thinking I would...
- add about 3.5 lbs of Borax to bring pH up to about 7.5
- wait on Alkalinity to see what kind of increase the Borax causes as I'm close to an acceptable Alk level now
- add 7.5 lbs stabilizer (split in three socks over the three returns) to bring CYA levels to ~ 30

So my questions are... first, does the above make sense? I hope to use the BBB method and hope to order a Liquidator with the 3/8" upgrade pretty soon, but in the mean time I can do it manually and supplement occasional evil 3" discs of chlorine and CYA with some caution. Is 30ppm a good target for stabilizer in this case? I figure low is better than high, at least in the sense that high is difficult to correct. Am I on target with the pH and Alkalinity or should I address Alk first?

Oh... the pool is partially shaded so it gets direct sun from about 11AM to 3PM give or take. I think that's also playing a role in my lack of stabilizer not being hugely problematic.

I should have taken photos each day, but the transformation really has been pretty dramatic. So thanks again for the wealth of information!

- Jason

 

[PoolGuyNJ]

Get the Alk level right 1st, then the pH.

If you are planning on using bleach regularly as opposed to 3" tabs, get the CYA level up to about 40 or 50. If you are using tabs, the CYA will rise as the season progresses.

Scott

 

[Ohm_Boy]

BTW, if your FC is high, like 10 or higher (and it looks like it is) you won't be able to trust the ph reading. It may appear higher than it really is.

 

[jreiser]

Get the Alk level right 1st, then the pH.

If you are planning on using bleach regularly as opposed to 3" tabs, get the CYA level up to about 40 or 50. If you are using tabs, the CYA will rise as the season progresses.

Scott

Thanks, Scott - that's very helpful. I'll start with the TA and address the pH after. I'm hoping to stick with bleach or liquid chlorine, but I don't want to bring my CYA levels up too much and end up requiring more bleach each day. Depending on budget I may have to rely on 3" tabs occasionally so I'm being careful to keep CYA on the low side.

BTW, if your FC is high, like 10 or higher (and it looks like it is) you won't be able to trust the ph reading. It may appear higher than it really is.

You know, I remember reading something about that, but I assumed that it was an issue associated with inferior test kits. Even if it's a little low, it's not dramatic, so I guess I'll wait until I can safely bring the chlorine levels out of shock before relying on a pH test.

Thank you both!
- Jason

 

[svenpup]

Keep in mind that your pH will tend to creep up when you are using bleach to chlorinate so don't be too eager to get it up. 7.2 is within range and you will be using muriatic acid to keep it down soon enough.

On the same vein, don't bring your TA too high as that will increase the rate of pH rise. I would shoot for the low end of recommended.

Also, you might want to add only 2/3 of the CYA you think you need and re-test after a week. The last thing you want to do is overshoot CYA level.

 

[jreiser]

Keep in mind that your pH will tend to creep up when you are using bleach to chlorinate so don't be too eager to get it up. 7.2 is within range and you will be using muriatic acid to keep it down soon enough.

On the same vein, don't bring your TA too high as that will increase the rate of pH rise. I would shoot for the low end of recommended.

Also, you might want to add only 2/3 of the CYA you think you need and re-test after a week. The last thing you want to do is overshoot CYA level.

Thanks for the advice! I'll definitely start slow with the CYA and only after I take some more accurate measurements of the pool. If it turns out the pool is smaller than I think, I could easily overshoot my target and that's no good at all. I'll start slow and measure in a week to see how it's going. I don't mind doing the chemicals in stages... as long as I can avoid multiple trips to the evil empire. People of Walmart scare me.

With a current TA of 50 should I shoot for 60 then? I could shoot for 55 with a little over 2 lbs of baking soda and retest in a couple days to see how that worked, and what effect it and the continued bleach is having on pH.

Thanks again!
- Jason

 

[frustratedpoolmom]

If your PH is stable then leave the TA. If you find the PH fluctuates too much then raise the TA to 60 and see if that helps.

 

[jreiser]

If your PH is stable then leave the TA. If you find the PH fluctuates too much then raise the TA to 60 and see if that helps.

Gotcha - I'm starting to understand this. It sounds like TA is sort of a buffer or stabilizer for pH, so if pH levels could fluctuate when total alkalinity is low. That would seem to be the reason to address TA issues before pH issues.

Thanks!!

 

[jreiser]

Levels as of Monday 6/21 @ Sunset:
FC=11.5
CC=0.5
TC=12
pH=7.3
TA=70
Stabilizer<20 (probably zero or close to it)

I had shocked the pool about six hours prior up to about 13 so that looks pretty good -- just a small drop from the sun and killing algae.

I cleaned the entire pool, added just 2 lbs of CYA in stockings over the returns to slowly begin adding some stabilizer to the pool. I'd have used a bit more but Walmart had nothing more in stock. Better to be safe with this stuff anyway.

Any idea why my TA level jumped from a noon reading of 50 to a 7PM reading of 70? In both cases I used water from the same location away from skimmers and returns and elbow-deep water. Given that pH has been relatively stable and is now on the rise slightly, I'm not going to do anything but continue to monitor both TA and pH. If the pool wants to adjust itself naturally I'm fine with that.

Thanks!
- Jason

 

[svenpup]

Levels as of Monday 6/21 @ Sunset:
FC=11.5
CC=0.5
TC=12
pH=7.3
TA=70
Stabilizer<20 (probably zero or close to it)

I had shocked the pool about six hours prior up to about 13 so that looks pretty good -- just a small drop from the sun and killing algae.

I cleaned the entire pool, added just 2 lbs of CYA in stockings over the returns to slowly begin adding some stabilizer to the pool. I'd have used a bit more but Walmart had nothing more in stock. Better to be safe with this stuff anyway.

Any idea why my TA level jumped from a noon reading of 50 to a 7PM reading of 70? In both cases I used water from the same location away from skimmers and returns and elbow-deep water. Given that pH has been relatively stable and is now on the rise slightly, I'm not going to do anything but continue to monitor both TA and pH. If the pool wants to adjust itself naturally I'm fine with that.

Thanks!
- Jason

The test is ±10ppm (1 drop) so 50-70 really isn't that big of a swing (60 ± 10 = 50 to 70). A slightly different sample size could account for that. At any rate it sounds like you are on the right path, and sometimes doing nothing is the correct action (not that a pool store would ever tell you that).

 

[jreiser]

Tue 6/22 1PM:
FC=9
CC=0
TC=9
pH=7.2
TA=70

Following the testing, I added 1 182Oz container of 6% bleach to bring FC up to about 12 since the pool is still a bit green and I want to kill off the algae and swim in a few days. I'll test again and give the pool another cleaning in a few hours and see how it's coming, but so far so good!

Here's a couple photos from when we opened the pool and one I took this afternoon (1 week after opening).

[attachment=1d85oz0f]day-1.jpg[/attachmentd85oz0f]
[attachment=0d85oz0f]day-7.jpg[/attachmentd85oz0f]

 

[jreiser]

Tue 6/22 7PM:
FC=8.5
CC=0.5
TC=9
pH=7.3
TA=80

I added another 182 Oz bottle of 6% bleach to keep the pool in igh shock until revisiting it around Noon-1PM on Wednesday (target FC of 11.5). The water is looking better every day! We had a rain storm this evening but I'm confident we'll be swimming this weekend.

The new grill's all set up and a friend is bringing over a pool beer pong set as a housewarming gift, so with a little luck clearing the remaining algae, we'll have a great weekend.

- Jason