Doing the Ascorbic Treatment

[pgjohnson]

Hi,

Pool: pebblecrete and SWG, +- 48000 liters
PH usually around 7.8 / 8 and chlorine around 5/7 with CYA around 30.

Have some very light staining mostly near return jets. Have tested with vitamin C tables and removes stain but larger areas so thinking I need to do the Ascorbic treatment.

Just concerned with taking the chlorine level to 0 and how low it can stay there before algae appears. Looked at a free bottle of algaecide i have but it is copper based which from reading would not be good to use. Is there a product suggestion from an Australian based members or is chlorine level of 0 ok for a few days? Do I have to take chlorine down to 0?
Last time shop measured copper in water they reported 0.2 (presume ppm) and within range of 0 - 0.3?

Also any Australian members have suggestions for the Ascorbic acid and sequestering agent?

Also found this product (Culator Metal Eliminator | Aussie Supplier | Lowest Price) which seems like its used/developed in USA?

Any help appreciated. Thanks

 

[ajw22]

It is questionable if Culator is effective. There is no science supporting it. It seems to have a placebo effect.

@mgtfp @AUSpool @aussieta can answer about effective algaecides available to you. We recommend PolyQuat 60.

Algaecide - Further Reading

www.troublefreepool.com

 

[JoyfulNoise]

If you can wait until the water temperature drops below 60F (15.5°C) then the grow rate of most algae species becomes very very low. If you do that and add a polyquat-60 algaecide, then you should be good for 24-36 hours. You need to isolate your pool equipment from the ascorbic acid (heaters are the most prone to damage) and then get the FC back up as soon as the stains have lifted. You must use a metal sequestering agent when raising the FC or else the metals will reoxidize and form stains again. It is best to dump as much of the water as possible after stains have lifted and refill with metal free water.

Do you know the source of the metal in the water?

 

[pgjohnson]

Possibly from salt bags added but not sure. Have not added salt for a while.

 

[mgtfp]

Zodiac Supreme Pool Algaecide is Polyquat 60:

Zodiac Supreme Pool Algaecide | Direct Pool Supplies

Keep your pool crystal clear with Zodiac Supreme Pool Algaecide. Say goodbye to algae and hello to a sparkling clean pool. Shop now at Direct Pool Supplies.

www.directpoolsupplies.com.au

 

[pgjohnson]

Awesome thanks

 

[pgjohnson]

Any suggestions for the best ascorbic acid and sequestering agent in Oz.

 

[mgtfp]

I only ever used ascorbic acid to remove stains in the attached spa and I just bought a small quantity at the chemist for that, but might be a bit expensive for larger quantities.

No experience with sequestering agents.

 

[Tena]

If you can wait until the water temperature drops below 60F (15.5°C) then the grow rate of most algae species becomes very very low. If you do that and add a polyquat-60 algaecide, then you should be good for 24-36 hours. You need to isolate your pool equipment from the ascorbic acid (heaters are the most prone to damage) and then get the FC back up as soon as the stains have lifted. You must use a metal sequestering agent when raising the FC or else the metals will reoxidize and form stains again. It is best to dump as much of the water as possible after stains have lifted and refill with metal free water.

Do you know the source of the metal in the water?

Use sequestrant or use polyfill in returns? Sequestrant is a long term battle also from reading here. Polyfill would catch the metals and sequestrant can't be used for that method (again from reading).

 

[JoyfulNoise]

Use sequestrant or use polyfill in returns? Sequestrant is a long term battle also from reading here. Polyfill would catch the metals and sequestrant can't be used for that method (again from reading).

Polyfill really isn’t going to do much for light staining. You’re better off lifting the stains with vitamin C and then using sequestrant to hold any iron in solution.

If you have access to iron free water, then do a partial drain and refill to reduce the iron levels. Exchange draining works great for reducing the concentration of unwanted metals without affecting the water level in the pool.

I doubt the salt caused iron staining unless you have really poor quality salt where you are. If that’s the case, I would look for pool grade salt to replenish what you lose by draining as it should be higher quality. Water softener salt usually comes with a lot of dirt in it.