Cleaning Plumbing Scale by Lowering PH ???

[Zephyros]

Hello Everyone (& hopefully Chem Geek),
I'm getting ready to replace the 20 year old pool heater and filter along with a 5 year old grinding pump. The pool has blue stains and scale on it from the old heater. Also when I pulled one of the spa jets I found it had a brown scale on it.

Before I put in the new equipment and get it re-plastered, I'm wondering if I should lower the PH to 5, 5.5, 6 or something to try and "etch" out the old scale and loosen / remove any embedded copper in the plumbing that may come out later and stain the new plaster? If necessary I could bypass the heater while doing this to avoid any more copper getting into the pool?

To avoid future blue staining on the new plaster, from the existing situation, should I use "CuLator Metal Remover now (I saw Chem Geek had a thread on this) as part of my plumbing etch process, or since the water will be pumped out for the new plaster whatever copper residue will be pumped out so I don't need to worry about it?

Does anyone think this would work or just chance damaging the 20 year old PVC plumbing?

Thanks for your help and insight, Tom

 

[Guest]

Probably a better question for simicrintz, since his day job is pool plaster!

 

[257WbyMag]

Throwin' this out there...I wonder if bypassing the heater and then doing a sort of acid start might be beneficial?

 

[Guest]

The copper staining occurred most likely because you had allowed your water to get aggressive and it attacked the copper in the heat exchanger (assuming that is the only copper in your pool system). The other way of getting copper staining would be with the introduction of a copper algaecide. That being said, the chance that you have "loose" copper sulfite sticking around to come out later after a re-plaster is pretty nonexistent.

When do you plan on re-plastering the pool? I don't think there is any value in lowering your pH (and you would definitely have to bypass the heater at those levels or you will just create more copper staining), and you stand a good chance of damaging light rings or other metallic items by getting it too low.

To avoid this happening again, keep your water chemistry where it should be and do not add copper based additives. Blue pools like yours do not exist except by chemical damage. You can avoid that from happening without "products", unless you have high copper levels in your fill water.

 

[Zephyros]

Hi Everyone,
Thanks for the replies and ideas, keep them coming.

Simicrintz, very good tips thank you. I'm the fourth owner of this house with the pool, so I'm unsure of the history, the pool was like this when I bought the place. The heater seems to be the only source of copper, see my sig for the equipment types. I'm planning to replace the equipment in the next month or two and then have the pool re-plastered in the spring.

Good point on the light rings, they are the only metallic items I have. I may replace the lights with LED anyway so perhaps this does not matter?

What about 257WbyMag's idea for a start up style acid wash? I would just pour a lot of acid into the pool water (if so, how much?). Would this also really just lower the PH as well?

But, as you said "That being said, the chance that you have "loose" copper sulfite sticking around to come out later after a re-plaster is pretty nonexistent." Am I just wasting my time? Does the brown scale on the Spa Jets not matter, I could just replace them? the pipes at the skimmer and at the pad don't look to bad on the inside, I'm just concerned of any residue in the pipes messing up a new $7,000 plaster job?

Your experience and help is greatly appreciated, Tom

 

[Guest]

Your plaster, from what I can see in the picture, is at its serviceable end. Pretty much anything you do now is a waste of time and/or money. An "in pool" acid wash like 257WbyMag suggests would clean things up a bit, but is usually reserved for more durable (and in better shape) finishes like PebbleTec, for example. Plaster just does not have the strength to handle acid washes very well, especially once degraded as much as yours. Lowering your pH to 7.2 for a while will help you take the scale off and back in to solution.

Where exactly in So. Cal. are you (and my apologies if I have already asked! You can PM me if you don't want it public as well)? Your pool is not real large by your sig, and if you are considering regular plaster only the price seems a bit high.

If you are committed to getting this work done, I would just hold off and wait until you re-plaster. Put the money you would be spending towards that work, and once you have it done adhere to the practices here and you will have a nice pool for many, many years.

 

[Zephyros]

Hi Bruce,
I'm about 100 miles north of you (see some older PMs we traded). The $7K is for:

Universal White Cement / Finest Finish® Marquise Series: Blue Pacific Color
http://www.finestfinishpools.com/products-marquise.html
or
Gemstone Polished Series — Light Blue Mist (I believe this is the same color as the Marquise Series: Blue Pacific)
http://www.gemstonepools.com/galleries/ ... emist.html

I was told that Gemstone uses the Universal White products, I just looked and see that at the bottom of the Gemstone page it now shows Universal Pool Supply LLC, so I guess the story I heard that Gemstone used Universal products and that Universal was buying Gemstone were true.

I was not thinking the acid bath was going to help the plaster in the least, as you can see it's bad. I thought maybe 257WbyMag's idea of using the acid would help clean things up. But I'm not sure, since acid would raise the PH, and you mentioned to drop the PH to 7.2 to remove the scale, by this do you mean the scale in the plumbing or on the plaster?.

How low could I go on the PH before it damages the lights? Would 7.2 be low enough to clean out the plumbing?

Bruce, one other thought, on the old Gemstone site they had a gallon product to use for surface maintenance, would that do any good now? (I searched and found McGrayel Company Startup-Tec, maybe this is the same product as it looks connected with Greg Garrett.)

Thanks, Tom

 

[Guest]

I apologize, Tom, for not remembering that we had discussed location It seems that I speak to so many folks every day that it is hard remember them all! Sometimes it helps if I can put a face (or pool!) to a name, but not always!

The current company that I bid plaster work for Poolscape Unlimited) uses the Finest Finish line, and it is a good product; definitely a step above "regular" plaster. However, if I was offered the choice of it or PebbleTec at the same price, I would choose the P-Tec. That would assure you of having the company (P-Tec) stand behind you and that you would be getting the best applicator and a great company to fall back on should you need something down the line.

Lowering the pH will tend to "soften" the calcium everywhere, so yes, it would most likely help with whatever is in the pipes. At 7.2 you should not see any copper or metal damage, but you should benefit from the softer calcium. Do not let the pH rise back up or you will scale up again. Instead, I would suggest that you stay in the proper range afterward to try and hold the calcium in solution until the re-plaster when they will drain the water away.

I have seen the "secret sauce" before also (we have it at Poolscape, but I don't know how much it gets used). I would imagine it is something similar to Jack's Magic, but I wouldn't swear to that! At Poolscape we are currently experimenting with doing the plaster work, letting the pool cure out and then going back in 30-45 days later and doing a R/O treatment to remove whatever is in the water and balance back to ideal. I don't have full results back yet, but we are optimistic that this will provide a better water balance, and a longer life expectancy of the finish. The point is that if you have proper water chemistry (like preached here), I doubt that you would need the "secret sauce" or much else to get the longest life out of your finish. Water chemistry is the key!

 

[chem geek]

As for getting rid of any copper that may still be in the water in ionic form (i.e. not as a stain), you'll be replacing the water when you replaster and that's the most reliable way of removing metal ions (an Reverse Osmosis process would also do that, but for replastering you'll be draining anyway).

The CuLator is not cheap (though for your size pool it isn't terrible) and hasn't been proven out yet on this forum. Also, there's no point in using something like that unless you've had a metal test done that clearly shows copper ions.