I have some spot stains developed over the years

[jp4120]

Couple questions..this is the first year I haven't used the frog mineral back....I have some spot stains developed over the years - rust/orange spots the size of a silver dollar or smaller - scattered around. also about 3 x 3 ft of stain around the drain in the deep end. that I thought was organic but hasn't faded from chlorine over the years.
today started using ascorbic acid in a sock - removes the stains in the shallow end in about 2 minutes - leaves a mottled look (not very noticeable)
1- do you think spot treating the stains this way without using a sequestering agent will prevent return of stains?
2- is it normal that the AA causes a black or grey stain sometimes - that seems to fade in an hour or 2?
3- do you think the stains are from the metals used in the Frog mineral pack?
4- would spot treatment of AA in a sock be able to treat a 3x3 area at the deep end drain?
I am a little concerned about a full treatment of the pool that requires low chlorine levels during the heat of the summer.
any

 

[JasonLion]

1) No. You might get lucky, but removing the stains increases the metals in the water which increase the odds of new stains unless you use sequestrant.
2) Sometimes if there are copper stains they can do that.
3) That is certainly a likely source, but they could have come from other places as well. Spot stains are often from a small piece of metal that fell in the water.
4) Eventually, sure. But it gets kind of tedious.

 

[jp4120]

Ok it seems these are copper stains
I'm probably gonna dump 5 lbs of AA
In but first reread instructions and pick
up a sequestering agent
Is that the recommended course of action?