Metal staining question

[Pennypacker]

Hello everyone. I was initially posting about this in the algae threads but not getting many answers. I have some light staining on my vinyl liner which I suspect is iron. Vitamin C removes it instantly. After reading the absorbic acid stain removal steps on this site, , I have a few questions hopefully someone can answer.

If I treat with AA can I then drain some water to remove some of the metals or should I just use a sequestrant, or both? I do fill with well water but have had my fill water tested many times and have zero trace of metals. I know well water can change suddenly and I'm assuming that happened or it was always there and I feel after raising my PH while chlorine was rather high, the stains appeared. Either way, the stains are there. Also, after the AA would my filter grids collect some of the metals?

My current numbers are;
FC: 18
CC: 0.5
PH: 7.4
TA: 110
CH: 200
CYA: 40

My FC is currently high because I Initially thought the stains were mustard algae and am currently coming down from a subsequent slam.

I also heard that if the staining is not heavy sometimes the sequestant would remove the stain? I just need some guidance on which course of action to take. I'm not against leaving the stains either, as my liner is 13 years old and will be replaced in the next few years. I really hate adding all these extra chemicals. If the iron is stained I don't think it would pose any threat to swimmers but I'm unsure.

Thanks in advance to any help offered.

 

[YippeeSkippy]

The stains are only cosmetic. If you chose to do nothing you'll be fine too. If it were *me* and I knew the liner was going to be replaced fairly soon, I'd live with it. Once you start with the sequestrants you would have to re-dose it routinely or bam! the stains will re-appear.

Did you ever use copper containing algaecides? They are often a source of metals when folks don't have metals in their fill water yet have used them.

Maddie

 

[Pennypacker]

I recently used a silverside but the stain was already there at the time and I thought it was a stubborn algae I couldn't remove.

 

[duraleigh]

The iron is harmless to swimmers.

Your well water is the source of the iron and iron will be in your pool as long as you use the well for your source.

 

[Pennypacker]

Minus a stain ID kit, can I be sure it's iron though? I could be wrong but always thought that copper was not as harmless to swimmers

 

[duraleigh]

It's iron. Copper would NEVER be removed easily with AA and would be a dark stain. A pic would confirm it but it's iron.

Did you put in copper in the pool?

 

[Swampwoman]

Why not pst a picture of the stains? I'm with Duraleigh on ths in that its most likely iron

If you decide to do anything at all, you might find that directly applying AA in a dishwasher sponge wand to the stain area is quicker and easier than the full AA treatment. Swapping water from a well may not be worthwhile if that's the source of trace iron, which I suspect.

If you want to find out if sequestrant will remove the stain, do the Metal Magic sponge test in this link. I've had success with both approaches.
http://www.proteampoolcare.com/images/uploads/MetalMagicSpongeTest.pdf

 

[basod]

Like swamp woman stated with the dishwasher sponge that's an easy way to touch up stairs and moulding. If you have larger areas a solution if AA in a clean garden pump sprayer can be used under water just pump it above the water and spray away the stains.
I modified an old o cedar hardwood floor mop head to directly apply AA and added a pvc vacuum ring around it to draw the AA up and out of the pool water so as not to deplete my FC in the process.

 

[Pennypacker]

Thanks for everyone's replies. I'm really torn on what to do. I might just live with it knowing that the liner is in it's twilight years but maybe I'll try sponge test. I really don't want the expense or trouble of constantly adding a sequestrant. Been running this pool for 10 years with the same fill water and never had any metals. I know that well water can change suddenly and that it has to be the source of the metals.

if I perform this sponge test, I'm assuming I should still lower the chlorine? I know I can lift the stains easily but then wouldn't I need to add a sequestrant? I know all these questions have been answered and I have been reading as much as possible. Especially the thread with the guy from Georgia. You guys and gals are the best. Really a special site here!!

 

[basod]

No need to lower your FC if directly applying the AA. It will neutralize some your FC so retest and adjust after cleaning.
its up to you on the sequestrant I've never used any and just run pH ~7.2-4 after cleaning the stains will reappear slowly just wipe or spray them off when they're bugging you.

 

[Swampwoman]

^Penny was referring to doing the metal magic sponge test, not AA.
With that said, for the test itself I don't see a need to lower it