Stonescapes Aqua Blue finish turned black

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Please note that ascorbic acid is not very good at lifting copper stains in the presence of an oxidizer (chlorine). It will often turn black copper oxide stains brown which, in the case of this pool’s current surface conditions, could be difficult to differentiate.

To the OP - this looks like a situation where your service company was using a copper based algaecide on a regular basis and you are now seeing the very expensive downside effects of that. Even if you treat the pool with Jack’s Magic Copper protocol, you’re talking about hundreds of dollars in chemicals and then a complete water exchange. There is no way to remove copper from water, it can only be sequestered and held in solution. The only way to be truly rid of it is to replace the contaminated water with fresh water.

I suggest you reconsider your reliance on a Service company. They are often many times more expensive than doing the maintenance yourself and their business model is based on reactive solutions to problems, not proactive preventative maintenance. Up to you entirely but TFP rarely ever recommends using pool service companies.
 
I just want to add re ascorbic acid test...

-- if it cleans it promptly, likely iron (but would normally only blacken with a bonding issue)
-- if it darkens black, then eventually turns kinda brownish, likely copper, which is at the moment, the prime suspect ;)
-- if by comparison, dry acid left on a spot actually returns the blue, then it again suggests copper and suggests that an underwater acid wash may work to remedy color ONCE the contaminant has been identified and can be eliminated

There is a tool on amazon to do an underwater acid wash with a little siphon and wand like a vac nozzle. I'll link you to it once we have an idea on source/contaminant/elimination strategy ;)
 
Update:

Electrician was out here, no bonding issues (whew).

Talked to Jacks Magic, Here is what they said:
"I feel confident after discussing the history and viewing the photos that the staining and scale is directly attributed to Ph control issues created by the dissociation of salt.. "


  1. Lower Ph to 7.2 and alkalinity no higher than 80ppm for a minimum of 4 months.. It will be easier to control ph with Chlorine Tablets and salt system off..
  2. I need you to add 1 bottle of the magenta stuff asap..
  3. I need you to add a maintenance dose of magenta of 8-12 oz per week for 4 mos..

thoughts?
 
fredpamm said:
Talked to Jacks Magic, Here is what they said:
"I feel confident after discussing the history and viewing the photos that the staining and scale is directly attributed to Ph control issues created by the dissociation of salt..
Click to expand...
That doesn't make any sense.

The dissociation of salt happens when you add salt. The sodium and chloride ions separate when the salt is added to the water.

Adding salt is pH neutral.

From then on, the sodium doesn't do anything. The chloride loses an electron to become to become chlorine and then another to become hypochlorite or hypochlorous acid.

Then the chlorine gains two electrons to become chloride again.

What Jack's said provides no usable information. They don't even suggest what the staining is.

I think that it's probably copper staining.

Does any metal in or around the pool show any corrosion?

Metal such as lights, handrails, ladders, pumps, screws, equipment etc.

Try the ascorbic acid on a test spot. Then try dry pH down on a different test spot.
 
I sincerely doubt calcium scale would be that uniform in color and your water would have to have had a very positive (> +0.7 for months on end) CSI to generate it. JamesW is spot on, this looks like metal scaling. Their suggestion is to basically lower the pH and TA of the water to make it more "corrosive" towards metals and then use a sequestrant to increase the solubility of metal ions in solution. It could very well work BUT it will require an ongoing battle to keep the pH and TA low AND and on-going cost of using weekly maintenance doses of sequestrant. There are folks on here who have real metal problems with vinyl liners because they live in areas with fill water that has metals in it. They must regularly use LOTS of sequestrant (gallons per month) in order to hold the metals in solution. The stuff is not cheap as the good sequestrants can run upwards of $40/quart.

If you can confirm that you have metals in the water then I would do a one time treatment that gets them back into solution and then dump the pool water immediately. Refill with known-good (ie, metal free) water and then make sure your service company is NOT using any metal-based algaecides.
 

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In my opinion, a pH of 7.2 is not likely to do anything to remove metal stains.

To remove metal stains, you would have to go really low like a no drain acid wash.

You would take the system offline and remove any metal from the pool. Low pH is very corrosive and will etch the plaster and any metal. It's not a great choice due to the risks.

Then, if the stains lift, then you can drain and refill.

Draining is risky because the pool can float if the ground water is high.

Alternatively, you can try Jack's #2 and then drain and refill.

Also, I understand that you probably don't feel like you should have to deal with this. You're paying so called professionals to maintain the pool and it should be right.

I imagine that you have probably lost all confidence in the service people since they don't seem to be willing or able to do anything to fix it.

In my opinion, when you lose confidence in someone, it's time to cut them loose and do it yourself or get someone else.
 
Okay, glad the bonding is good. That eliminates a particularly worrisome source ;)

I'm not sure what to make of Jacks advice either but if in essence they're saying you had an extended period of high ph I actually agree that is likely and has contributed to or exacerbated the staining.

With metals, its common to control the ph to 7.2ish, particularly when applying products that require it.

But what did they say about #2 not working on it and making it worse? And when bring salt dissolution into it, are they actually suggesting your plaster has efflorescence caused by the salt? That only happens if its left sitting in a pile and wouldn't explain the uniformity of the stain. Maybe in his reference to salt dissolution he was just trying to explain why with swg you need to control the ph.

What I also find odd is that they're recommending Magenta, which is not HEDP-based, when you already have Jacks Purple in the water, which is HEDP (phosphonic acid). My understanding is that the two shouldnt be mixed because they can cloud up. But you have bigger fish to fry here so that's not a major concern.

HEDP is generally the more effective sequestrate but Magenta is good for picking up plaster dust etc on startup. There are other benefits to using a non-HEDP sequestrant such as avoiding the possibility of building up phosphonic scale on your swg.

Did Jacks say why they recommended Magenta over Jacks Purple? They've told me in the past that Purple is specifically formulated to work in saltwater pools...and their regular products they say won't work in "high TDS" pools...which by attrition a salt pool is (because salt reads as a dissolved solid.) However, Magenta is formulated for salt.

To my mind the best way forward here will depend on your metal test. Treating with Jacks Magenta and controlling your ph tightly can be a part of the plan either way but I'm not sure it will work without additional stain removal action.

If testing shows high levels of copper, you should do a partial drain to at least dilute, if not a total drain, coupled with a stain removal strategy and sequestering anything you lift (because with a metal stain that you lift, the metal goes back in solution needs to be sequestered.)

If you a) test positive for copper and b) stain responds to dry acid, you could try this tool to perform what is a semi-equivalent to an underwater acid wash.
https://www.amazon.com/Purity-Pool-UAW-Underwater-Acid/dp/B00C7UGLFY/ref=pd_cp_23_2?_encoding=UTF8&pd_rd_i=B00C7UGLFY&pd_rd_r=SW5B9FRFYTNYGWDB31QV&pd_rd_w=DqAFI&pd_rd_wg=b6XvN&psc=1&refRID=SW5B9FRFYTNYGWDB31QV

If, however, you're still concerned that the finish itself has failed, or if you want to get I guess some dedicated intel on the case, and or f the metal treatment strategies dont work, I'm wondering if this is something you could reach out to OnBalance for a professional consult.

OnBalance is a member here who has a research co. by the same name. Kim and his team have written a lot of papers on plaster and impacts of pool care and are considered industry experts. I don't know how far they go in staining issues, but the company might be in a good position to evaluate the manufacturers claim.
 
fredpamm said:
Update:

Electrician was out here, no bonding issues (whew).

Talked to Jacks Magic, Here is what they said:
"I feel confident after discussing the history and viewing the photos that the staining and scale is directly attributed to Ph control issues created by the dissociation of salt.. "


  1. Lower Ph to 7.2 and alkalinity no higher than 80ppm for a minimum of 4 months.. It will be easier to control ph with Chlorine Tablets and salt system off..
  2. I need you to add 1 bottle of the magenta stuff asap..
  3. I need you to add a maintenance dose of magenta of 8-12 oz per week for 4 mos..

thoughts?
Click to expand...

A bit off the path, but how did he qualify the bonding??
 
Update: The pool builder had a reputable repair company come out. They did the standard three tests for metal staining. No result. He then poured a bit of Muratic acid on the top step to see if it would do anything. Nothing . Then he did a scratch test with a screwdriver. That turned up the blue. He is perplexed nd is going to call all companies involved

Stay tuned.
 
Fred, if it did not respond to any of the tests, you might want to check out my earlier suggestion to reach out to OnBalance, or at least direct your PB to OnBalance's website. The team is pretty good at sleuthing out plaster problems and are on the leading edge science-wise.

Here's a link: Pool Help Information and Research for Pool Owners and Professionals. Kim Skinner is a regular contributor to TFP.

Also, possibly weird question, but do you or any of your neighbors have well point pumps or well pumps? I once read of a "mystery stray current when bonding checks out" situation where the culprit reportedly was a well point submersible pump with wiring exposed to the water, located half a mile away. It feels like you've had some kind of "plating" here.
 
Swampwoman - I remember that stray current incident & “plating” has been on my mind too.

I asked how the bonding was qualified, because the typical residential electrician is unlikely prepared to qualify a bond grid. Splitting the bond wire & simply “ringing” continuity is not the test.

Large spools of wire must be run from any metallic elements over 4 sq inches within 5 feet of pool walls & associated Mechanicals.

If this pool has a wet niche, water must pumped down below for a test.

I am not going to detail the test procedure. I don’t think it is appropriate to this forum.

This work is best left to a competent pool contractor (as it is not a line voltage test, for licensing purview) or an electrician familiar with the quirks of the test. Industrial electricians may equipped for the test, since they work in factories & are very familiar with bonding.
 
^Yeah, you're likely thinking as I am that typical metal staining simply isn't that uniform, at least in my experience...tends to follow flow patterns.

There is a good article over on Aqua Magazine outlining bonding grid testing I think, geared to in-industry folks, Fred, if you'd like to point your PB in that direction. I agree it's not typical DIY fare.
 

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