Metal Stains....

[Sharkyy]

For 3 months these orange/yellow stains have been popping up all over the bottom of the pool. Tried ascorbic acid treatment which had no effect. Thought maybe the rebar was too close to the surface...then found the culprit. A roofing nail from nearby construction has been pushed around the bottom of the pool staining as it goes and blending in with the stains so we never saw it when brushing. The roofing nail is gone now - but there are probably 50-60 individual metal stains on the plaster. What's the best course of action here? This thing has been floating around for months now so god knows how much metal has seeped into the water.

The particulars:

Colored Gemstone plaster
Ph - 7.5
FC - 2
TA - 80
CYA - 40 (being raised now that winter is over)
Calcium - 210
Salt - 3200

 

[JasonLion]

Try placing a vitamin C tablet directly on one of the stained areas. If that removes the stain in that local spot, then it is possible to get an ascorbic acid treatment to work.