Ugly Ugly Pool Stains

[schuter]

Awesome site, and thanks to those who come here to provide help. Much appreciated.

Last year I was in a rush to close the pool. Freezing temps were coming and I was preparing for some travel. I was in the middle of a algae problem so I shocked covered it....figured I would deal with it this spring.

I opened to a green swamp two weeks ago. I immediately went to work on it and finally got it cleared up...problem is that I can get the algae stains to come off. I have been at shock levels for two weeks and it is barely touching the stains. I wont say slam levels because my test kit doesn't read that high, i'm much higher than 12 for sure. TF-100 kit will be here Wednesday.

At this rate, it might be Fall before I get this cleaned up. Any thoughts on a quicker way to remove the stains other than drain and acid wash?

As I said before, the TF-100 kit will be here Wednesday so I don't have all the readings. I know my FC is somewhere above 12.

Thanks
Schuter

 

[woodyp]

I think it's gonna be easier to wait until AFTER you pass all 3 criteria for the SLAM process and then deal with the stains. Holding FC high enough and long enough for the SLAM may take care of a lot of it. Brush, brush, brush. Welcome.

 

[pooldv]

Welcome to TFP!

Acid wash is a last resort and is fairly destructive and will shorten the life of your plaster. There are other things to try first.

Read this
Diagnosing Pool Plaster Problems
and this
Pool School - Metals in the Water and Metal Stains

I agree that waiting until after the SLAM is best.

 

[schuter]

The TF-100 arrived today.

FC - 15
TC - 15
PH - 7.8
TA - 180
CH - 175
CYA - 70

I have not added chlorine since 6-3-16. I reduced the SWG down to 50% and have reduced the pump run time down 6 hours per day while I waited for the TF-100 to arrive. Since its been at least four days and the TC is still the same as the FC, should I still go through the SLAM process? Any other numbers stand out?

Thanks
Andy

 

[pooldv]

The PH test isn't valid when FC is above 10 ppm. TA is very high, that combined with rising PH can lead to scaling.

The way to determine if you need to SLAM is to perform the Overnight Chlorine Loss Test.

 

[Casey]

You're going to have to keep your FC elevated a bit and brush your pool daily to make a dent in that organicically stained pool. This year, take the time to close the pool properly and you won't have to look at that ugly staining next year.

Good luck!

 

[schuter]

I've had the FC extremely for at least several weeks. The pool started green and has been crystal clear for about 10 days, with the FC levels still high. I've brushed daily, even with a stainless steel brush with no change to the stains. When I clean the pool cleaner it is almost like green sand that is coming out of it. I've spent lots of $$$ on chlorine and after looking back at pictures from the beginning I can say the stains haven't changed a bit. I checked the FC tonight and its at 12.5. See what it is in the morning. I would think it is going to drop a little with the amount of pollen we have in the air. Everything is yellow and you can see a layer floating on the surface of the pool. It might be time to call someone in on this...

 

[Rcckks96]

Have you done the vitamin c test?

 

[schuter]

Have you done the vitamin c test?

Yes, negative results. I guess I should go buy a puck and try that test... I'm about 95% sure its from the algae issue I was dealing with late last season.

 

[Swampwoman]

Shutter, you fill from well. There's a chance you have a combo stain. Eg metal plug organics and maybe a bit of scale. They're tougher to remove, especially iron scale stains. Do you have any dry acid to try in a sock? If so, try that for a while and THEN try vit c again on the same area.

Or see if MA helps reduce...but be careful handling. Some crazy folks will soak a sponge in MA in a bowl, turn upsidedown in water and et that sit on a stain -- wear gloves and hold your breath if you do this please. Or get either the spot removal tool or underwater MA acid wash tool to try...would be cheaper then a drain/acid wash:

Amazon.com: Purity Pool UAW Underwater Acid Wash Set: Patio, Lawn Garden

Amazon.com: Purity Pool OS Out Spot Stain Remover, Model: OS , Home Personal Care

If you do THAT treatment and you still have organics, eg tannin, left over, sunlight, time and chlorine will fade same IME. But ya gotta make sure the sunlight and chlorine can get to the stains

 

[schuter]

Ok, so I drained the hot tub and took some close up of the stains. I think it might be scale that is green from the algae...if that makes any sense???? Where the green is spotty it is as rough as 80 grit sandpaper. It gets a little smoother where the stains are more dense but you can tell its only because the surface is covered with the green at a greater uniformity. Its very hard, when I scrape it off it feels like green sand. Where the green is very light when you run your finger over it it feels like grains of sand stuck on the surface of the plaster.

I tested a spot with MA and it removed it...took about some time but the surface wasn't real dry either.


- - - Updated - - -

 

[Swampwoman]

Given your spot test, I would be inclined to try the purity underwater acid kit if you can locate one. That way you could do a treatment to reduce the scale, then see if light/FC lightens what's left, or if vit c works, or if simply a second treatment works.