Is this black algae, or stains, or???

[Holmes0412]

A little background, this pool was built in 2017 and is gunite. I'm gustimating it is +/- 12,000 gallons? The house was a foreclosure when we bought it this past April, and it sat vacant for over a year. I think the owner stopped taking care of the pool 1-2 years prior to that, so I believe that it sat untouched for +/- 3 years. I have never owned a pool and didn't know what to do, so I waited until a local pool builder/cleaner could come check it out. They had the pool from a swamp to crystal clear in a little over a week. They vacuumed to waste as much of the growing algae as they could every day and then hit it with large amounts of Leslie's power powder plus and alum after a few days of the vacuuming. The attached pics show the progress. The black stuff on the walls is the only thing remaining to really deal with. It is all the way around the pool on all the walls, but none of it is on the floor. I am guessing because of all the power powder he put in there settled to the bottom and killed it all off? There's light staining on the floor and there are patches of gunite that is missing or damaged form the neglect.

I have tried to rub the walls with a chlorine puck after brushing with a steel brush, and you can see where I went over it randomly one time in the pics. It came off everywhere I rubbed the puck, so does this mean it's for sure black algae? Or is it stains from all the other algea that didn't come off like it did on the floor?

What's the best way to cure it if it's black algae? I don't think it's feasible to scrub almost every inch of the walls with a puck. What do you think?? Tia

 

[JamesW]

Probably copper.

Stain ID Kit | Jacks Magic

jacksmagic.com

 

[Holmes0412]

I apologize for the low quality photo's, It was dusk, and they have been cropped. I can try to take better pics if needed.

 

[JamesW]

This looks like a mineral cartridge, which contains copper.

 

[Holmes0412]

Thank you James, I will order the test kit. Leslie's is at the end of the road, but every time I bring my water in they state their machine is messing up and giving everyone a reading for copper, so I have never actually tested the water for it

 

[JamesW]

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[Holmes0412]

Would copper stains go away by rubbing them with a chlorine puck like the stains did in the pics? Also, why would it be only on the walls?

 

[Holmes0412]

Got in with the goggles today to run a puck on it again. Noticed that most of the walls are covered in a hard yellow like scale almost, and In between were all the breaks in that there are raised bumps and black dots. What could this be?

 

[JamesW]

Did you get the stain id kit?

 

[Katodude]

If you pick at it does it come off?

 

[Holmes0412]

I ordered the kit same day, but it still hasn't came in yet. I have no tried to pick at it, but can try to see if I can peel some off this weekend and will try to get a picture

 

[Holmes0412]

So when we checked the mail yesterday, I finally got my stain ID kit in but did not have a chance yesterday to do it. I did try to snap a few pics of the yellow stuff all over the walls, see below. You can see the black spots in-between where the scale is not at. And idea of what I am looking at here? Another odd thing is in the pic with the return jet it in, there is a line straight down the wall where there is no build up. I thought that was strange, no clue why it's like that.

This stuff does not scrape off with just a fingernail.

 

[JamesW]

Probably copper.

Probably copper and iron stains.

See what the stain ID kit shows.

 

[JamesW]

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[Texas Splash]

Yeah, quite a mess you inherited. Take it one step at a time. Test with the ID kit as James recommended. You already know you have some organic staining confirmed by the puck testing. Rubbing some cal-hypo on some areas might be a good organic test as well. Rub some areas with a Vitamin C tablet to test for iron. Very possible some of if those things are covered by scale as well.