High TA

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20brnat15

0
Mar 24, 2015
9
Garland/Utah
I am currently working with pool used by the school during the day and the public in the evening. don't know how to get the TA down to where it ought to be.
PH- 7.4
FC- 3.0
CC- .8
TA- 325
CH-375
CYA- 0
Use a BECSys5 chemical controller
Test Kits- Taylor K-1518 for chlorine, Taylor K-2005 for PH, TA, and CH
need some sound advice.
Thanks
 
Welcome to TFP!

Assuming you have a regular water replacement schedule, normal for a public pool, and naturally high TA fill water, then there is nothing you can do about the TA level. It is going to be high no matter what you do. All you can do is maintain the PH somewhere in the 7.3-7.4 range with frequent acid additions. Acid feed automation is likely your best choice.

Measuring your fill water TA, if you haven't already, is a good step.
 
It's been since April 2015 the date of my last post, and not much has changed with the pool I take care of except I now am experiencing small patches of algae
in the grout lines in the shallow end, and in the gutter. I can't get rid of it. When the pool is vacuumed it is brushed as well with a metal brush.
How can I get rid of the algae? (The chlorine levels are kept between a 2 or 3 ppm)
 
Welcome back!

Is the algae below the water line or above the water line?

20brnat15 said:
It's been since April 2015 the date of my last post, and not much has changed with the pool I take care of except I now am experiencing small patches of algae
in the grout lines in the shallow end, and in the gutter. I can't figure out how to get rid of it. When the pool is vacuumed it is brushed as well with a metal brush.
How can I get rid of the algae? (The chlorine levels are kept between a 2 or 3 ppm)
Click to expand...
 
today the TA is 275 ppm, calcium 400 ppm, ph a 7.5, chlorine at 2 ppm.
I use Sodium Hypochlorite as my disinfectant, and Co2 to keep the ph down

- - - Updated - - -

there is no water replacement schedule. It was was built in 1982 and to my knowledge has only been drained twice in that time,
and that was done to make repairs
 
The algae can be resolved with more brushing.....a lot more brushing. I would also elevate the chlorine, Do you use CYA? How much?

What is the TA of your fill water? What is the CH of your fill water?
 

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Part of the problem is the CO2. CO2 lowers the pH without lowering the TA.

So, your TA stays high and creates more pH rise so the CO2 gets used up faster.

You're probably spending a fortune on carbon dioxide.

I would switch to muriatic acid for a while to reduce the TA.

You're at risk for scaling. Check your CSI by using Poolmath and keep it between -0.3 and +0.1.

Are you getting any combined chlorine?

What is your cyanuric acid level?

What is the water temperature?

What is the salinity of the water?
 
In answer to your questions,
Yes I have high chloramines by my tests .6 to .8 and I've never been able to get them below a.5 for very long maybe a day.
The CYA with the tests I have is between a 0-30 range. Water temp. varies between 83 and 85 degrees
and I've never heard the term salinity as part of swimming pool chemistry.
Kelly
 
Sodium hypochlorite has a lot of salt. Knowing the salinity can help determine how much sodium hypochlorite has been used since the last refill and how much dilution has happened from water loss and refill.

I'm thinking that the salinity is probably pretty high. If you can get a salinity reading using a K-1766 test kit or a digital meter, that would help.

A heavily used indoor pool really needs a supplemental system, such as UV or ozone to break down chloramines.

I would suggest that you get a UV system to help with the chloramines.

I would recommend that you switch to muriatic acid for a while for pH reduction until the TA gets down to about 80.

I would suggest that you get regular dilution from water replacement.

You're probably getting a lot of contaminants in the pool from bathers that are combining with the chlorine that's reducing the effectiveness of the chlorine.

Has the pool ever used bromine?
 
I have been trying for years on my own to get my CC down to a.2. Right now according to the test results it is a .8. When I shock the pool, in the morning
it might have gone down to a .6. I guess what I am asking is how do you shock, super chlorinate, or slam a pool (i guess all those terms mean the same thing)
so as to get rid of the CC?
 
If you are getting high use on a daily basis, you will probably never be able to get the CC down to zero with just chlorine.

You need a more advanced system designed by someone who does commercial high use indoor pools.

Most likely, you will need a professional ozone or UV system.

If you are not getting adequate dilution of the water, you're probably getting a buildup of various compounds that register as combined chlorine.

Compounds might include chlorine or bromine combined with nitrogen or carbon based molecules, chlorate or bromate etc.

I would suggest that you consult with a professional qualified to design and install a system to address the need of a high use indoor pool.

A professional UV system and adequate dilution should improve water quality.

5.5 Dilution
Coagulation, filtration and disinfection will not remove all pollutants. Swimming pool design should enable the dilution of pool water with fresh water. Dilution limits the build-up of pollutants from bathers (e.g. constituents of sweat and urine), of by-products of disinfection and of various other dissolved chemicals. Dilution rates need to account for the replacement of water used in filter backwashing, evaporation and splash-out. As a general rule, the addition of fresh water to disinfected pools should not be less than 30 litres (8 gallons) per bather.

http://www.who.int/water_sanitation_health/bathing/srwe2full.pdf
Click to expand...

Did you test for salinity?
 
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