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How to Get Iron Out of Hot Tub Water

By: Author Jeff Campbell

Posted on  - Last updated:

Categories Hot Tub Maintenance

Millions of people get their water from a well and many of these either own or will buy a hot tub. Since well water often contains iron and other metals, I wondered how to get iron out of hot tub water.

To get rid of iron and other metals in your hot tub water, use a product designed to eliminate metals from water such as Spa Choice Metal Free Stain Remover. Iron in hot tub water can interact with chlorine and turn your hot tub water green, at least temporarily.

But that’s just a quick snapshot.

CLICK HERE to check out Metal Free Stain Remover on Amazon.

So here’s some good news: iron in your hot tub is not going to harm you! However, it can cause other problems, and you will need to address these issues.

So in this article, we’ll look at exactly what those problems are, and exactly what to do to fix it.

Carry on reading to find out what those problems are and what you can do to make your hot tub water as clean and clear as it can be.

How do I know if my hot tub has too much iron?

You’ll know if iron is present in your hot tub water as the water will turn green when chlorine or bromine is added. But if you want to know specifically how much iron is there, take a sample to a nearby pool and hot tub supply store for testing. 

Metals such as iron occur naturally in water, and especially well water.

It is also possible to find traces of iron and other metals in main water systems, especially if the pipes are old. However, the bottom line is this.

It doesn’t really matter that much.

Iron in your hot tub water is not going to cause you any harm. What it will do is discolor the water and stain the surfaces of your hot tub.

You will know if your hot tub water is rich in iron or other metals if it becomes discolored, and yet it remains clear. You will also see staining on the surfaces.

Now if it is cloudy, you may have to oxidize it.

Oxidizing your hot tub is the same as shocking it, and I covered this in a recent article. In fact, shocking the water can even help clear the water that is discolored from iron or other metals. But there’s a right way and a wrong way to shock your hot tub.

You can read it here on my website by clicking on the link.

Does iron make the hot tub water cloudy?

Iron will discolor the water, but it will not make it cloudy. If you have cloudy water, it is more likely to be the result of a chemical imbalance.

Cloudy water is most often caused by using a non-chlorine sanitizer, pH levels that are too high, or a problem with bacteria and biofilm build-up in your plumbing.

Iron will not make your hot tub cloudy, but it will produce a rusty brown tint to the water. Although sometimes it may appear green.

This is caused by the iron-oxidizing with the chlorine.

So if you see a slight green colorization of your hot tub water, but the water remains clear, and you find staining on the surfaces of your hot tub, that is a sure sign you have a problem with metals.

Foam buildup in your hot tub is another indicator that there may be a chemical imbalance in the water.

And you can read more about that by clicking on this link to a recent article on my website. Foam can sometimes indicate high pH levels, so you need to check this out first.

Anything over 7.8 is too high! So just click that link to read it on my site.

Foam is not in itself bad for you. It may be caused by contaminants such as body lotion, deodorant, shampoo, cosmetics, or laundry detergent. But any chemical imbalance could lead to skin disorders and a burning sensation in your eyes.

You don’t even have to submerge your head to feel this. The tiny droplets given off when you run the jets are enough to sting your eyes if the pH is too high.

How do you remove iron stains from a hot tub?

If you already have stains in your hot tub from iron in the water, mix equal parts water and white vinegar and add 1-2 TBS of baking soda and mix well. Using a rag or mild scrubber, dip into the mixture and scrub where the hot tub is stained. Wipe with a clean, damp rag when done.

When iron and other metals are allowed to remain in the system, you will get a buildup of deposits on the surface, which will appear as a stain.

The best way to treat this is to prevent it from happening in the first place.

Maintaining the balance of your water is the key to this, which means checking the pH and alkalinity levels regularly. Using a sequestering agent such as Spa Choice Metal Free Stain Remover (click to see on Amazon) will prevent minerals from being oxidized by the chlorine and stop the water from becoming discolored.

Cleaning and changing your filter regularly can also help remove some of the iron from your hot tub.

How often depends on the type of filters your hot tub uses. Check out this recent article here on my website to find out more about changing your filter.

Just click on the link to read it on my site.

What other metals cause problems in hot tubs?

Aside from iron, you may find copper or manganese in your hot tub if you are drawing water from a well or other ground source.

Copper can also cause corrosion of metallic equipment in your tub and is characterized by a green, gray, or turquoise tint to the water.

Copper is used as an algaecide because it effectively eliminates algae and is relatively inexpensive, but if you use too much, it can create other problems. And honestly, unless your hot tub is kept uncovered, you’re not likely to have algae problems as pool owners do.

If you notice a purple, black or dark brown tint to your hot tub water, that is a sign that you have manganese in there, but this is not as common as iron or copper.

Using natural water sources for your hot tub water is not a problem in itself.

But it can lead to problems, so you need to know what those are and how to deal with them. With a few simple precautions, there is no reason why you can’t enjoy a calm, relaxing soak in your hot tub without any worries about metals in the water.

The good news is that Spa Choice’s Metal Free Stain Remover (click to see on Amazon) will prevent issues from any metals in your water.

What is the best hot tub metal remover?

I prefer Spa Choice Metal Free Stain Remover, but there are many products that are available to eliminate metals from hot tub water and prevent staining. 

CLICK HERE to check out Metal Free Stain Remover on Amazon.

Not only does it prevent iron and other metal stains, but it also removes metals from the water completely thanks to its highly concentrated formula.

It is easy to use – just add 1 16 oz bottle whenever you refill your tub, for large-sized hot tubs.

It is compatible with all sanitizers – bromine, chlorine, ozone, and other natural products – and very simple to use. Once the tub is full, though, you will need to run the pump for at least 30 minutes to clear the jets.

Final Thoughts

If you are in an area that relies on well water to fill your hot tub, I hope this article eased some of your concerns about iron and other metals.

As with any hot tub, it is all about taking good care of the water.

If you want to keep your water clean and crystal clear, you have to look after it, and if it starts to get a little cloudy, that’s a sure sign that something isn’t right.

You don’t always have to change your water. If this happens, sometimes shocking, it will do the trick, but you should change your water anyway 3 or 4 times a year.

In a recent article, I discussed this in some detail – read it on my website by clicking on the link.

If there is anything I might have missed or if you have any questions, don’t hesitate to contact me or leave a message, and don’t forget to check out the links to other articles on my website.

Jeff Campbell
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