Blue well water 6

[beach004]

There's been one previous thread on this, but it was not dispositive, so I am trying for help. I live in Piedmont North Carolina, on a well: Unfiltered, untreated. It's been tested, none of the numbers out of whack, pH not low; but the water, when seen in a white five gallon bucket, has a distinctly blue tint; and the toilets and sink will get a blue ring around the drain and the rim, over time, that nothing, not even muriatic acid, wants to dissolve--I have to scrub it out with lavastone. I do have copper pipes; the house is 14 years old. Anyone have a clue?
Beach004

 

[mbmarsh]

That makes sense, from the (little) chemistry I remember; the chlorine would oxidize the metallic copper, converting it to, I suppose copper oxide; that would then be more susceptible to acid converting it on to copper bicarbonate. At least, it did in 1961...