Purple/Dark Spot/Stain

[JamesW]

Assuming the CYA and copper levels are high, you will need to do substantial dilution to prevent a reoccurrence if you can get the stains to come out.

Is the pool vinyl liner?

If nothing works, you can try lowering the TA to zero, but that's a huge risk for damaging the liner and equipment.

I don't recommend a zero TA treatment, but you can do it if you feel like it is worth the risk.

Be ready to replace the liner if nothing works or just live with the stain until you need a new liner.

 

[RichyRich50]

Hello all,

My apologies for my absence, had some things come up.

So still have the purple stain/spot issues. I also tried the Vit C tablets that @JamesW recommended.

Findings: no change. I tried multiple times to rub the tablet on the spot and nothing happen. The stain did not get smaller or darker. Please see attachment for vit c tabletS.

Also please see attachment for new pool results. My copper did come down to 0.4Ppm. I started at 0.8ppm.

 

[JamesW]

Try pure vitamin C.

If that does not work, you can try one of the suggested treatments, but be aware of the risks.

 

[RichyRich50]

@JamesW could you show me what Vit C will work? I did an Amazon search for pure VIT c. I will attach a link. Please let me know if that will work?

Amazon Elements Vitamin C 1000mg, Supports Healthy Immune System, Vegan, 300 Tablets, 10 month supply https://a.co/d/b6NvaMr

 

[JamesW]

Just pure vitamin C from any store.

 

[RichyRich50]

@JamesW so I found the pure vitamin C. Please see image for reference. I tested two methods and nether seems to work.

Test 1: took 1 tablet and rubbed it against the stain. Nothing happened.

Test 2: took about 50 tablets and crush them inside a sock. Use that to rub the stain. It looked like the stain got lighter but was hard to really tell due to my goggles getting foggy. But I would say nothing happened.

On that note what would you recommend I do next?

 

[JamesW]

Can you just live with the stains?

If not, you can try citric acid, oxalic acid or sulfamic acid.

Note that any treatment for copper can sometimes make the stains worse, so all treatment chemicals need to be tested on a spot first.

All treatment is at your own risk based on your own research.

Assuming the CYA and copper levels are high, you will need to do substantial dilution to prevent a reoccurrence if you can get the stains to come out.

Also, sulfamic acid will convert all FC to CC for about 3 to 6 months.

Is the pool vinyl liner?

If nothing works, you can try lowering the TA to zero, but that's a huge risk for damaging the liner and equipment.

You can take the equipment offline during treatment.

I don't recommend a zero TA treatment, but you can do it if you feel like it is worth the risk.

Be ready to replace the liner if nothing works or just live with the stain until you need a new liner.