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Removing & Preventing Spa Shell Stains

Even if you’re doing everything right, a spa can develop stains. The trick is preventing them in the first place. This article will provide tips on preventing and removing those stains that can develop on the shell of your spa.

Preventing stains developing on the spa shell

Spa stains can develop from a buildup of rust, calcium and scum in your spa water. So let's look at how we prevent that from happening.

Preventing Rust Build Up

Rust stains are caused by iron, copper and chlorine reacting with one another in your spa water. As these elements react, they oxidise, leaving greenish-blueish-blackish stains on the spas shell.

We can prevent this by using a metal sequestrant. A metal sequestrant will clump the metal molecules allowing them to then be filtered out of the water by your spas filtering system. Make sure you follow the instructions on the sequestrant bottles label.

Preventing Calcium Build Up

Calcium build up shows itself as a scale deposits that form on the side of the shell. The cause of this is calcium and magnesium build up in the water, becoming hard and then fixing itself to the shell surface and fixtures of the spa.

To prevent calcium buildup from occuring, we can purchase calcium hardness reducer and following the instructions on the label. We can also make sure we consistently balance our water chemistry.

Preventing Scum Build Up

Spa filters remove do a great job of filtered out body residue, metals, bacteria, chemicals, dust and debris, However they can only do so much. If contaminants are left in the water long enough they can form a layer of scum on the water surface and a ring around the hot tub shell itself.

It is important to test and adjust the sanitiser and pH levels of your spa on a frequent basis. These tests should be performed prior to each use of the spa. At a minimum it is recommended that you test the spa water each week, regardless of use. Simply test your water weekly with test strips, or more often if you are experiencing a scum issue.

For a detailed guide on preventing spa scum, you can read our article om what causes hot tub scum.

Summing Up

Preventing spa stains developing is our best way to enjoy a clean stain free spa experience. But if you do develop stains, just follow these simple steps and make sure to be consistent. Happy soaking!

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