Drained pool, help ID these stains on surface

[tangouniform]

I've been dealing with a staining issue the past couple years that I haven't been able to remedy so I decided to drain this year to see if I can get a better look at the stains and to see if I can tackle the issue. I'm dealing with two separate stains here. The entire gunite surface is covered in what looks like a green stain which is shown in the pics. I also have a lot of brown staining at various parts of the surface which is shown as well. Last year I tried a no-drain acid wash which did pretty much nothing. I also tried the vitamin C and chlorine tablets on the stains last year to no avail. Any help?

BTW, all these pics are taken after I pressure washed the entire surface.

 

[JamesW]

Looks like multiple issues including copper, iron, scale, etching and it even looks like the pool was painted at one point.

I would suspect that the chemistry has been all over the place.

 

[tangouniform]

Looks like multiple issues including copper, iron, scale, etching and it even looks like the pool was painted at one point.

I would suspect that the chemistry has been all over the place.

Anything I can do right now while the pool is empty to make the surface look better?

Would an acid wash help or possibly hurt considering the condition of the surface?

 

[JamesW]

The surface is in rough shape. An acid wash might clean it up some but will make it very rough.

Not a lot of good options.

 

[DeanP66]

My pool had similar stains to those(probaby worse) about 2 months ago and I decided to drain and do an acid wash. It was pretty easy once I got the water drained and although my plaster has seen better days, it cleaned up nicely after the acid wash. I just used a watering can with about 8 gallons of Muriatic acid (full strengh) and diluted it in the watering can with water to about 2 to 1 acid to water ratio. I poured about a 7 to 10 foot section at a time and scrubbed it with a brush as well and hosed it off toward the deep end where my utility pump would pump it out of the pool. When I finished the entire pool I did a little touch up in spots that I wasn't quite pleased with and when finished, I refilled the pool. Came out really nice.

 

[tangouniform]

Thanks for the replies.