Removing stains from white plastic... and keeping them away

[P00LNerd]

The white plastic of our skimmer and stairs both have a gray shadow above the water line. It's especially visible on the stairs, where a warning label about diving recently came off, and the area under the label is still bright white.

From what I've read on this site, I suspect the staining is the result of copper from 90-day algae control and silver in the "Mineral Pac" of our former Frog sanitizer. Please correct me if wrong.

I also believe the "Scale and Stain" product provided by my pool installer, which we use at 5 oz/ 15k gallons every week, is probably a sequestering agent aimed at keeping these metals in suspension, and limit such staining. Again, please correct me if wrong.

We have removed the Frog system, but since the pool water already contains these metals, I was instructed to keep using the sequestering agent ("Scale and Stain"?). I guess this must continue forever?

Looking at getting rid of the stains, what would I use to remove them from the glossy white plastic of the stairs? I don't want to chance anything harsh, which could etch or degloss the plastic. I'm wondering if scrubbing them with the weekly 5 oz. of sequestering agent diluted in a 2 gallon bucket, might be a safe and effective method.

 

[ajw22]

Try a Magic Eraser.

Magic Eraser on Pools - Further Reading

www.troublefreepool.com

Getting a scum line in the skimmer is common. I doubt it is due to your metal worries.

 

[P00LNerd]

Thank you, ajw22! I'll have to see if my wife already has some of those, or pick some up at the store to try.

But just to be clear, this isn't what I'd call scum. It really does look like it could be a thin plating of silver on the fiberglass stairs, at least my imagination tells me that.