Tiny white flakes in Pool

[Charlie Bezzina]

TexEd, one of you are using the incorrect temperature scale and I suspect that it is Paulo.

86 degrees Celcius = CSI 0.58 and an incredibly hot pool at that.

 

[Paulo88]

I thought that the chance of a "miracle fix" was too good to be true

Also I deleted the app and all its data and re-entered everything and I too now get -0.14 Strange ?!

 

[Charlie Bezzina]

Paulo, you owe me a miracle if my pool ever self destructs.

 

[TexEdmond]

Okay. So now that we've solved the mystery of the CSI, it's a good idea to start looking at getting rid of the scale in the SWG. I notice another user in this thread was able to simply remove the cell and rinse it out really well. If you use any acid to remove the scale, you'll also remove some of the cell material itself, which will reduce its overall life.

One other issue that might help longterm: Some members here have found that adding borates to their pool greatly improves their SWG life as well as further improving the feel and sparkle of the pool water. Borates help keep the pH of the water from rising rapidly, which is the cause of scale formation in the cell itself. This is a double edged sword though. It also means that if you have high TA fill water and are fighting constantly rising pH you'll have to add double the amount of muriatic acid to drop pH, but less frequently. It looks like your TA is coming down fairly easily from the numbers you've posted here, so you may be a good candidate for borates.

I'd recommend you get some granulated CYA stabilizer and add it as needed to get a higher number and keep the leftovers in a dry location, because you'll use it over time to bring those levels back up. This will help your pool hold FC longer and you can keep your numbers at a higher level, which will allow you to dial back on the SWG and pump runtime like we discussed earlier.

GREAT JOB getting things under control so quickly. You're almost there!

 

[Paulo88]

I'd recommend you get some granulated CYA stabilizer and add it as needed to get a higher number and keep the leftovers in a dry location, because you'll use it over time to bring those levels back up. This will help your pool hold FC longer and you can keep your numbers at a higher level, which will allow you to dial back on the SWG and pump runtime like we discussed earlier.

I think this is the key. I'm still having to have my SWG at near 60 - 70% to maintain a good Chlorine value. I'm hoping that increasing the CYA I can get this down to 30 - 40%.

 

[Paulo88]

So I did another full weekly test yesterday and all the results were around the same as before, which is pretty good. However this doesn't seem to have resolved the amount of flakes Im seeing in the pool.
I was going to clean the SWG cell but I've done this before but it scales up again in pretty quickly.
I was wondering if it could be something that I've not tested for ? I've heard that phosphates can build up in the SWG. Is this something worth testing ? I have the kit already.

 

[mknauss]

Push your TA lower. I have found when CH is above 400 ppm, TA is a big factor.

 

[Paulo88]

Thanks mknauss, I will look into lowering the TA.

Also, I went ahead and did the phosphate test too, it was high... like 4000ppb high.

Is this something to be worried about ?

View attachment 378618

 

[mknauss]

If FC is kept up based on the FC/CYA Levels, phosphates are of little concern.

 

[Paulo88]

do you recommend muriatic acid or dry acid/PH Reducer ?

 

[mknauss]

Muriatic acid.
Dry acid adds sulfates. Sulfates destroy metals -- aka your SWCG.

 

[Paulo88]

Thanks I will order some now. But I'm a little confused on adding this with my ph being only 7.4
Do I need to raise my ph first or should I add the muratic acid until the TA is lower and the raise my ph back to 7.4 ?
is there a ph level I should never drop below ? 7.0 ?
Is there an easy calculator to easily show how much acid to add to lower the TA ?

 

[TexEdmond]

Do you have any water feature or spa spillway on your pool? If so, turn those on while your pump is running to aerate your water. This allows more carbon dioxide to be released from the pool, which raises pH and lowers TA. It's two sides of the same coin. I don't know how much acid you're normally putting in your pool but if you're seeing a relatively stable pH and not adding acid often, you might be a good candidate for borates. This will further stabilize your pH from moving around and also keep your CSI low even when pH rises.

Correct, never drop below a pH of 7.0. If you're going to drop it to 7.0-7.2, make sure you're aerating by either swimming, turning on water features, even turning your return nozzles upward so they break the surface of the water. Your SWG will help aerate as well. While continually aerating, don't add any more acid until your pH naturally rises back up to 8.0. Then check your alkalinity again and recalculate your CSI. The lower your TA goes, the longer it will take for pH to rise back up. Making wide swings in pH like this will have a better effect on lowering the TA. Have a look at this article, it also includes several ideas for aerating if you don't have a spillway or fountain.

Lower Total Alkalinity

A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.

www.troublefreepool.com

Borates in pool - Further Reading

www.troublefreepool.com

 

[Paulo88]

Thanks TexEdmond,
I do have a spa at the end of the pool and I admit it's not had as much use lately due to the colder weather. I will run it today for a few hours to see how that helps the pH. There are also a couple of return nozzles that already break the water so I'm good there.
As far as acid is concerned I haven't added any myself as of yet. I know the pool guy would do that occasionally but I never saw him measure or test. To be honest I feel he was just throwing in a gallon here and there whenever he felt like it. Another reason why I decided to take this on myself.

 

[Paulo88]

I intend to go buy some muriatic acid this weekend in order to lower my TA.
In the meantime I'm steadily raising my pH which is currently hovering around 7.4 - 7.6 I'm hoping to get it to 7.8 by the weekend aka more spa time, its a hard life

I'm presuming that I should then use the Pool Math app to calculate how much acid I need to add in order to reduce the pH from 7.8 to say 7.6. Then test the TA.
If more is needed re-calculate pH 7.6 to 7.4, retest TA.
Rinse and repeat until I get to 7.0 pH or I get a good TA ?

I've also read that its quite common to add lots of Acid to new plaster pools, is this true ?

 

[TexEdmond]

You might not see a noticeable change in TA just lowering the pH by 0.2 so save your test reagents. It'll be more noticeable if you drop a wider amount; going from 7.8 to 7.2 you might notice some TA is neutralized by the initial drop, then more TA will be slowly used up by the steady rise as you aerate back up to 7.8.

It's more noticeable for folks with very high TA and they need large amounts of acid to do the swing from the 8.0 range down to 7.2. Since your TA is lower, it'll take less acid to drop your pH down, but when mine was over 100 it took almost a gallon of acid to do this a few months ago.