How to remove sequestered metal from water.

[Phil.c]

A couple of years ago my indoor liner pool developed brown staining at the deep end, I bought commercial pool stain remover, it removed the stain but it came back after a few days throughout the whole pool and including the steps etc, I tried this a few times and also by adding products to keep the stain returning to the liner, these worked for a while but didn't stop the stain returning.

I have tried a different method, now I must say that I'm not a pool expert but the method below has worked for me and it's now three weeks and there's no trace of a stain

So, this is what I did:-

I turn my pool off in October so the water was cold, but I see no reason why it wouldn't work with warm water.

The chlorine was 0 this is important because apparently it can stop AA from working, everything else was as normal.

I bought some Ascorbic Acid https://www.amazon.co.uk/dp/B00LOM2YLQ/ ... 11_TE_item and with the filter set to circulation added about half a pound, after a few hours check the stain as more may be needed until it's totally gone, best to leave overnight instead of adding too much from the start.

Once the stain has gone I switched the filter back to filtrate, I bought 3KG of hollow fibre polyester pillow stuffing, my skimmer has a basket, if yours hasn't then it's a good idea to get a cloth bag to put the fibres in, these are added to the skimmer and pushed down inside and just below the water line so it's possible to see that the water is still swirling and the fibres are not stopping the flow.

I changed the fibre every day until it was all used up, it's possible to re-use it by washing it out with clean warm water and then giving it a spin and a tumble dry, but don't put it in the washer as it will end up in clumps.

After a week, because the ph is usually lowered with AA, I raised it but very slowly, in my case, half a cup of ph raiser granules a day, I also raised the chlorine slowly.

It's now three weeks since I started, this morning I vacuumed the pool because there was some green algea buildup, but it's looking good and there's still no sign of a stain and the steps are "white".

From now on, periodically, for a week or so, I'm going to add fibre to the skimmer, just to keep things at bay, if it can filter metal then it should also filter small particles in the water.

I hope this helps, if I've forgotten anything please let me know.

[Denniswiseman]

Time will tell as sequestered water can take a while before the sequestrant stops working

[Phil.c]

Something I forgot to mention, there was no visible staining on the fibers when they were removed for new ones, however, all the used fibers were put into a cloth bag, after a few days the bottom of the bag where the water collected was brown

[Denniswiseman]

Sounds interesting but could just be the water in the fibres leaching out
If it works it will be a good breakthrough

[Phil.c]

Well we shall know in another few weeks, the thing is, when I got the stain off the liner twice before it was back in a few days?

Interesting too that the fibers are hollow!

[Denniswiseman]

Well we shall know in another few weeks, the thing is, when I got the stain off the liner twice before it was back in a few days?

Interesting too that the fibers are hollow!

Did you add a sequestrant after the previous attempts

[Phil.c]

Yes, No more metal, but even if it worked for me it's not a fix as the sequestrant would need to be added for the long seeable future which is good earner for the pool supply people!

[Denniswiseman]

The sequestrant should have lasted more than a couple of days
I have seen videos of that fibre product being used effectively but in a heavily contaminated brown water

[Phil.c]

As I said the stain was back in a few days, probably four or five, my stain was not what I would call heavily contaminated, more of a light to medium brown stain, but everywhere.

[Phil.c]

The metal hasn't retuned to the liner at all and it's now close to five weeks so I would say that this method of removing sequestered metal from the pool works.

[Poolswim]

The metal hasn't retuned to the liner at all and it's now close to five weeks so I would say that this method of removing sequestered metal from the pool works.

Did your staining ever come back?

[Phil.c]

Not in nearly eight weeks, after that the liner split, it took twenty years for this to happen So in answer to your question, No.