new to BBB, need help w/ high CYA and CH

racingmommy

New member
Jun 11, 2010
3
Hi all,

I am new to the forum. Thanks for all great advice I have taken from the Pool School so far.

I am maintaining FC by using bleach. No other chemicals have been added to the pool water since spring opening apart from pH adjustment w/ acid.

Last week temperatures have picked up (88°F), and I had cloudy water.

pH 8.0
TA 130

I added HCl until pH 7.6. Water was still cloudy , so I added 1gal HCl to lower TA (don't know where to get aeration device).

Now the water is sparkling, BUT:

FC 0.0
pH<7.0
TA 80ppm
CH 550ppm (up from 330ppm, I have no idea where this comes from!)
CYA is >100


Tap water is
pH 8.0
TA 50ppm
CH<50ppm (not a significant source of Ca to my pool.)

Now my pool water is too acidic to swim, and I need to add Chlorine quick, or else... green swamp.

If I add soda ash, I will increase Carbonates, water will get cloudy again. I was considering Borax to raise pH. Does it make sense just to increase pH with Borax, or will I have to add the whole 50ppm Borax?!? Not sure if I want to do that since I live in a rental. (Now pool guy bc/ I don't want them to dump more chemicals in for no reason.)

Balancing water does not make much sense bc/ high CH will always cause my pool water to get cloudy. Still I need to get Chlorine into the pool quick - which one to use that is not destroyed by acid?

Is CH and TA reading (FSA-DPD test kit) influenced by water temperature?!? Do I get falsely high readings?

Confused, and grateful to anyone who shares their wisdom.
Dagmar
 

PaulR

LifeTime Supporter
Jan 11, 2009
1,966
Cupertino, CA
CH and TA tests should not be affected by normal pool temperatures.
You should use borax just to raise pH for now, don't need to do 50ppm borates.
I have to say, I wouldn't have expected calcium clouding given your numbers, but lots of people know more about that than I do.
--paulr
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
The first priority is to get the PH up to 7.0. The second is to get the FC level up around 10. The third is to get the CYA level down to something reasonable. With CYA above 100 you aren't going to be able to fight algae effectively. Replacing water to get CYA down will also lower CH, which will be a good thing.
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,941
San Dimas, CA (LA County)
The CH is coming off your walls. Mine has increased 400 ppm or so just by maintaing pH below 7.5 and CSI in the negatives. Some scale is dissolving back into solution.

Try rotating your returns up so you get a fountain effect, that will help aerate. If you have a jacuzzi, run it. Don't need the heat on, though.
 

racingmommy

New member
Jun 11, 2010
3
Thanks, guys, for your info! Yep, got some Borax to adjust pH. Really easy, highly recommend it (The numbers in the 'So you want to add borates to your pool' section worked just fine for me, thanks!!) Now the water is fine, and I will chlorinate later today.

Is there a rule of thumb on how 'old' pool water can get before replacement? My landlords may never have drained the pool at all in 10-20 yrs...

I agree, high CYA alone is a reason for water replacement... But where the *** do the high Calcium levels originate?!? Acid rain? Deteriorating plaster? The numbers went up from 300ppm last year to 550ppm this year. I just don't get it.

Thanks again, you guys rock!!
Dagmar
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
You don't need to replace the water unless you have a problem. High CH or high CYA are both common reasons to want to replace water. Some people never replace their water.

When you have CH in your fill water and lots of evaporation, the CH level will tend to go up over time. When tap water is added, it brings some CH along. But when water evaporates, only the water evaporates, the CH stays in the pool. Over time you are adding more CH and never removing any, so the CH level goes up.
 

frustratedpoolmom

TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
12,177
SWSuburban Chicago, IL
IF they haven't drained the water in a long time - the CYA level is likely very high since the test only goes up to 100.

I would replace 50% of the water, refill, recirculate and retest, repeat if necessary.
How is the pool chlorinated on a daily basis?
 

racingmommy

New member
Jun 11, 2010
3
I have found the Ca source - I introduced it myself by adding Cal-Hypo in the spring. I dumped about 10 bags over the course of a week into the pool to keep FC up for sanitation. The pool was really in bad shape then.

Did not think about the Ca level then, nor did the guy at the pool store give me a hint.

In the meantime, I have switched to bleach as my only source of Chlorine.

How long to replace 7.000 gal water?!? Temperatures are up, school's out, I can't close the pool for a week.

At least, with pH kept low for a day and the Borax added, the scaling is gone.

D.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
You can replace water a little at a time, no need to do it all at once. That way the pool will be swimmable the entire time.
 

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