Salt Cell Covered In Black Greasy Stuff!

by Mel
(Sydney, Australia)

My saltwater cell - which used to attract a white furry coating, is now covered in a thin coat of something black and greasy.

Any ideas?

Thanks for the question Mel

I'd like to have your complete chemical readings:

Chlorine, CYA (cyanuric acid/stabilizer), pH, Alkalinity, Calcium Hardness, and Metals (iron and copper). It makes troubleshooting much easier.

It could be a chemical issue or not. Are there any other areas of the pool that have this issue? It might be black algae if you have a plaster pool.

Have you been using any algaecides lately? Many of them are of lesser quality and use metal fillers such as copper. The cheaper algaecides will leave a greasy sticky deposit on vinyl liners.

Sticky Pool Algaecide On Vinyl Liner

Get back to me with the chemical numbers and I'm sure I can help.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Chlorine Generator/Salt Cell" category.

Check back to this post for updates or answers.

If you need immediate assistance (within 24 hrs) or for emergency personal assistance, you can make a donation of your choice and I'll answer your questions by phone.

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Hope this helps and have a great Summer.


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Black Mold and Pool Ionizer

by Thomas

I have an Ion pool with a vinyl liner that was installed approximately 2 years ago.

Recently I have noticed a blackish brown stain around the edges of the bottom of the pool.

Is there a way to treat this stain without replacing the liner?? I have seen similar questions here but all have been with chlorine treated pools and since my pool is an ion pool I want to be sure I do the correct treatment.

Can you help??

Thanks for the question Thomas

I have an ionizer link that you may want to look over:

Swimming Pool Ionizer

I know that many people want to go as chemical free as they can and I fully understand why. But, what you just described is a text-book issue with ionizers and metal based treatment systems.

What you're doing is adding copper to the pool. Some people have well water (high copper/iron content) and use an ionizer. Then someone else uses an ionizer, has well water, and uses a cheaper algaecide. The filler in the algaecide is copper. They're getting a triple whammy of copper. And then, guaranteed, the copper stains set in.

This is one of those things that the ionizer sales pitch doesn't tell you. The inevitable copper staining.

There's a product you can use. It's called Jacks Stain ID Kit. Get that and follow the directions.

An ascorbic acid (Vitamin C) treatment is probably what you need. You can find that at this link:

Ascorbic Acid

However, this is for chlorine pools. This might cost you some money and a good bit of work to get the stains removed. Unless you stop using the ionizer you will probably have this problems again.

You can also use a metal sequestrant. Metal sequestrants that are based on HEDP, phosphonic acid and/or its derivatives are the most effective. Please check with the ionizer manufacturer for specs. and see if this is the right course for you.

Some popular brands are Jack's Magic Blue, Purple, and Pink Pink Stuff, Metal Magic, Metal Free, & Metal Klear.

This is normally not a one shot deal. A metal sequestrant does not remove metal from pool water. It holds it in solution until it can get filtered. Then you backwash the metal out.

Because metal sequestrants break down over time and get filtered and backwashed out, you will need to add a bottle once per week.

Some people who sell ionizers will say that using an ionizer is a good way to control algae and also allows the pool owner to use a very low level of chlorine.

On the surface, this is true. I've seen lab studies on how free-floating pathogens can be killed with low levels of chlorine plus using an ionizer (copper and silver).

However, I think they fail to mention that, in real pools and real life, these pathogens are not free-floating. They almost always have a carrier, or attached to something stringy or gooey like snot, vomit, feces, and sometimes blood. I had to know all of this and have a proper pool decontamination protocol for the YMCA, which is subject to the Oregon Department of Health.

These attached pathogens are difficult to kill even with high levels of chlorine.

With an ionizer and very low level of chlorine, the chlorine can't do its job in any reasonable amount of time.

The chlorine gets eaten up very quickly by the carrier before it gets a chance to kill any pathogens. The ionizer is left to deal with the rest, but simply cannot. If you increase the ion rate to 0.6 - 0.8 you'll be adding more copper to the water and quickly precipitate copper staining.

Again, I know that you probably want to go green and use as few chemicals as possible. I do too. The only "chemical" in my house is toilet bowl cleaner. No Lysol, Comet, floor cleaners, etc... I mop the floors with a wet rag, have water filters in the showers, and have distilled bottled water delivered. We don't drink tap water.

But, when you have the correct relationship of chlorine/CYA, it can't be beat in providing a safe and clean pool. Nothing kills organic matter and bacteria like chlorine.

If you need immediate assistance (within 24 hrs) or for emergency personal assistance, you can make a donation of $35 for one hour and I'll answer your questions by phone.

If you've found this site helpful please consider making a donation. Thank you.

Hope this helps and have a great Summer.


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