Gents,

I purchased an existing home in December of 2013 and inherited a fiberglass pool.

Pool stats:
-18K gallons
- Chlorine
- New: Heater and filter (sand) in 2013

So it was un-opened for a year or two, after opening the pool this year it obviously took sometime to get everything sorted out and the only remaining obstacle is the metal staining (tested with vitamin C tablets and it promptly responds to Stain Free, etc.).

I've successfully treated the metal staining with "Stain Free" + "Metal Free" followed by a backwash within 48 hours, all while the chlorine is less than 1.0. The pool will stay stain free for 10-14 days and then the stain will return slowly and increase in color until it is fully visible (nearly original intensity). So I can get the stain to lift but the metal is somehow re-introduced. I've tested the tap-water and it is metal free, the heater does not have a bypass but the predominate culprit seems to be iron vs. copper.

So what is the source? I took a photo of our pool into the local pool shop and they called the "Stain Free" representative. Our pool is a bit unique and is built into a small hillside, two sides of the pool are protected by a sloping retaining wall (ranging in height from 6"-36") built of red-pavestone pavers that rise directly from the pool edge (i.e. no lip, etc.). The Natural Chemistry representative believe the iron is orginating from the iron oxide used to produce the red color of the pavers, we also have a water feature (waterfall) that originates from the pavers and most likely runs over some on it's way into the pool.

So here is the question, the latest treatment recommended was "Stain-Free" + "Metal-Free" + "Scale-Free" , backwash (24-48 hours) followed by a weekly maintenance of "Scale Free". But before I try this treatment I wanted to know if you guys think this will work without attempting to address the pavers (i.e. will the stain be maintainable without addressing the pavers in some nature)?

And if I need to address the pavers the only option ($) I have is to seal/paint the pavers which I don't mind doing I'm just not confident if only painting the exposed surfaces will be enough?

Thoughts?

Thanks in advance,

Philip Johnson