Stained pool?

[Sandia]

For the past several weeks we have had these stains on the pool bottom and steps... brushing and vacuuming has not removed them. The pool guy says it is the concrete showing through the plaster? I don't want to believe that (if I don't have to!) as it was just re-done 3 years ago by the previous owner...
I ordered a test kit from Jack's Magic, but it will take a while to get here.. Any clues?
The latest chemical readings were:
5 ppm free chlorine
5 ppm total chlorine
7.6 pH
120 ppm total alkalinity
50 ppm cyanuric acid

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[JamesW]

I don't see gunite. It might be scale or copper.

 

[mknauss]

Are those test results from you own test kit? Do you have a CH reading?

 

[JamesW]

It looks like you might have a few structural cracks.

Are you losing water?

 

[Sandia]

The results are from the pool company that comes once a week...
I think what you are seeing as cracks is the reflection of the power lines? not losing water...
I will try a better photo when the sun comes up, lol!

 

[mknauss]

If you wish to take care of your pool water chemistry and not have the issues you are having you need to do your own testing.

This forum advocate’s pool owner water testing using a proper test kit. Order a TF100 test kit. It is properly sized for the residential pool owner.

 

[splashpad]

The results are from the pool company that comes once a week...
I think what you are seeing as cracks is the reflection of the power lines? not losing water...
I will try a better photo when the sun comes up, lol!

1- I see that is power lines now that you say it. It's hard to see any "stain" or discoloration in that photo.
2- Definitely get your own complete home test kit (as already advocated), you can solve almost any imbalance when you can test on the spot!

 

[JamesW]

It looks a lot like copper staining.

Do you have a source of copper?

Maybe copper algaecide, a gas heater, an ionizer or other copper source?

 

[sktn77a]

Have you tried a "non-drain acid wash"? You basically add 5-20lbs ascorbic acid (depending on the water volume) to get the pH down below 6 for several days. If its a metal stain, that should help noticeably.

It could also be a bad plaster job - plasterers add too much CaCL to their mix to speed up curing - that can lead to "mottling" or a "blotchy" finish.

Fire the pool guy - he doesn't know what he's talking about. Take care of the pool yourself.

 

[Sandia]

Source of copper? Not sure... I do live in Arizona, the "copper state" and the water that fills the pool comes straight from the city pipes...
The heater is electric.

I have not tried an acid wash, I was waiting for the Jack's Stain Kit, or at least a tablet of Vitamin C, which I just got.

As for firing the pool guy, maybe!

Maybe easier to see on the steps, in the sun... definitely a grey-ish mottled apperance that doesn't scrub off

 

[Texas Splash]

I was waiting for the Jack's Stain Kit, or at least a tablet of Vitamin C, which I just got.

Try the vitamin C tabs crushed in a thin sock or nylon. If it helps, it's iron. If it gets darker - copper. Then you know. If the Vitamin C does nothing, try a chlorine tablet by gently rubbing around in a small area for a short time. Don't just let it sit in one spot too long though. If that works, it's organic staining from alage. Those are convenient at-home ways to test for some common issues. If none of those work, you can wait for the Jack's kit, but it may be plaster related.

 

[mknauss]

Is it smooth or rough to the touch?

 

[Sandia]

The bottom of the pool? relatively smooth...

 

[mknauss]

If the areas that are 'stained' are smooth, then it is most likely copper. Either copper based algaecides or tablets have been used or the pH has been kept very low and the heat exchanger is dissolving.

Scale would be rough to the touch.

 

[Sandia]

If the areas that are 'stained' are smooth, then it is most likely copper. Either copper based algaecides or tablets have been used or the pH has been kept very low and the heat exchanger is dissolving.
Scale would be rough to the touch.

The stained areas are slightly rough, but the same texture as the non-stained areas

When you say "the heat exchanger is dissolving" - what does that mean, please?

 

[JamesW]

If you have a gas heater, it usually has a copper heat exchanger, which can corrode due to bad chemistry or excessive water flow.

 

[Sandia]

Ah, no... we have a 6 month old, whiz-bang, AquaCal electric heat pump - I just update my signature line!

 

[YippeeSkippy]

How does your pool guy chlorinate your pool? Is he using tabs? Which ones, do you know?? Do you use anything in the pool with "Blue" in the name?

Maddie

 

[Texas Splash]

Post #11. Did you ever get a chance to do those?

 

[Sandia]

The vitamin C tabs did nothing...
The Jack's Kit arrived, but the water temp is below 60f, I will try heating it this weekend and attempt the kit