How to remove Black Buildup on Pool Stairs and dirty Walls

[Guest]

What I don't know is, is the AA treatment process the same, just substituting Citric Acid?

Yes.
They are both reducing agents, as is oxalic acid.
The black staining is most likely copper or manganese. My guess would be manganese from the water supply since copper is not that easy to lift. What surprises me is that the dry acid had not effect. It should have done the same. Because it did not it made me believe the stains were organic. Like I said in an earlier post perhaps it was not done properly.

The reason why you cannot just crush up vitamin c from the drug store is that the tablets are not pure but have binders and fillers in them. It actually becomes more expensive to buy it that way then to buy the pure stuff. You couild not just crush them and substitute it pound for pound. Also, the fillers and binders would be going in your pool. I am sure they would cause no harm but you never really know what they are.

 

[Guest]

So, as far as the abscorbic acid, does anyone see where it would be any different to just buy a couple bottles of vitamin C at a pharmacy and crush it up as opposed to the $50 half pound bag at the pool store?

2 lb jar of ascorbic acid from The chemistrry store is about $32
http://www.chemistrystore.com/cart.cgi? ... hild=49902
Citric acid about $8 for 2 lbs
http://www.chemistrystore.com/cart.cgi? ... hild=49908
Oxalic acid about $7 for 2 lbs (careful, it's toxic)
http://www.chemistrystore.com/cart.cgi? ... hild=49928

Any of them should remove the stains
You can also buy commercial products like Stain Free (expensive ascorbic acid)
or Pool Stain Treat (expensive oxalic acid) at the pool store.
Some pool stores that deal in commercial accounts sometimes sell ascorbic or citric acid in bulk for stain treatment.

 

[frustratedpoolmom]

Please post an update with new pics when you got it all sparkly.

 

[X1088LoD]

Will do, it will be a few days of course

Anyways, thanks so much for all the help everyone, I'm slowly but surely figuring this beast out!

 

[X1088LoD]

Ascorbic Acid Treatment- Oops, screwed up, now pool is green

Threads merged for consistency by Moderator

I did the ascorbic acid treatment on my pool (copper I believe is the culprit), and forgot to do the metal sequestering agent before re-chlorinating the pool (probably did too much to fast too).

I rebalanced everything this morning, and when I did start chlorinating it again today, the water turned pretty dark green. I believe this is because of the lack of the metal sequestering agent.

It was kind of shocking how quickly it went green.

I have 2 quarts of Metal Magic, do I just need to bring the pH down a bit more and apply the Metal Magic to get the green out? Or does it matter that I have all the chlorine in there at this point, do I need to let that subside?

Currently pH is around 7.2, Alk is 140, FCl is around 5, CYA is at 40

Help me get the water blue again!

Thanks

 

[frustratedpoolmom]

AA doesn't usually work on copper....why do you suspect copper?

Can you tell if the stains lifted?

You should just keep adding the sequesterant till the color improves, I don't think you need to lower the PH any less.

 

[X1088LoD]

I was just googling similar things that turn the water green like that, it seemed like copper was the culprit most of the time.

Just a thought to throw out.

Stains came mostly out, I probably needed more to get a few areas, but it looks very presentable now.

Will add the sequesterant and see how it goes.

 

[frustratedpoolmom]

Keep us posted. And update the pics

 

[X1088LoD]

How long should I anticipate it taking to start noticing a difference? Is this a several hour thing or overnight thing, etc?

 

[frustratedpoolmom]

Oh, didn't see this. I'm not sure. It's been a few hours though.... notice any improvement?

 

[X1088LoD]

Maybe a slight improvement, still green looking though, two 32 oz containers later

 

[frustratedpoolmom]

I don't think this is copper. I'm wondering if you should have the pool store nearest you test for iron/copper metals in general. Wondering if it would be a good idea to replace some of the water (again I know ) to lower the levels? If they are high wondering how much sequesterant you'll go thru in the long run....?

 

[Guest]

You have a pool with a blue liner, right? Iron will color the water yellow. Yellow + blue = green. Irin is the most common metal that ascorbic acid works on along with manganese. It usually is not that effective on copper but sometimes it will work. It really depends on the oxidation state of the copper stains. However, your stains did look like copper since they were black. The reason the water colored is that the chlorine re oxidized the metals in the water (that you did not deactive by adding sequesterant) into a colored state. Lucky for you the metal did not redeposit as stain. Just add another bottle or two of seqesterant and drop the pH to 7.0 for a few days and the problem should clear. Bring the chlorine level up SLOWLY!

I am assuming the color is clear and not cloudy? If there is any cloudiness it could be from the seqesterant or could be an algae bloom. What is your FC?