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  • Writer's pictureAqua Warehouse

How to combat soft water issues in hot tubs

Updated: Nov 11, 2023

In a hot tub, some calcium hardness is a necessity.

If the Calcium Hardness levels are too low, the water is under-saturated and will become aggressive as it attempts to obtain the calcium it needs. This “soft-water” will actually corrode surfaces inside the hot tub, everything metal in the hot tub can also gradually corrode from the soft water. This problem can be exacerbated if a hot tub owner allows the pool’s pH level to plummet and stay low for an extended period of time.

So while bathing in soft water may feel great, the soft water can greatly damage the hot tub. In this weeks blog, Aqua Spa Supplies, outlines what soft water issues are and how to combat these.

What is soft water?

Soft water is low in the minerals (especially calcium) that hard water is abundant in, but has a higher sodium content. Because it’s low in minerals, soft water has a tendency to pull in minerals where it can, which means that other contaminants get pulled in as well.

Why is soft water bad for hot tubs?

Never use soft water in your hot tub! If you do have to, you need to add something to increase the calcium hardness to prevent problems with your hot tub. Such issues can be the following if you use soft water:

  • Corrosion to soft areas of the hot tub

  • Can cause foaming issues can be a problem

  • Shiny areas of the hot tub will be corroded

Make sure if your water is soft water, that you add calcium hardness increaser to get it up to at least 180 ppm.

How can you combat soft water?

While hard water can produce stains and scale, soft water can be corrosive to the soft and shiny parts of your hot tub. It also leads to excessive spa foaming problems. Add Calcium Hardness Increaser when your spa or hot tub is less than 150 ppm.

Invest in the best spa chemicals

The best way to combat soft water issues is to regularly test and change your water. We recommend changing your water every 3-4 months. If you want to keep your hot tub in good condition and keep yourself healthy, you should change the hot tub water regularly.

Finding a cleaning regime to suit you and your spa can be challenging. At Aqua Spa Supplies, our team of experts are on hand to help you find the best spa chemicals to suit your needs. If you would like more information about spa chemicals or would like to shop the best hot tub accessories on the market, visit our website today




Jess Court

I'm Aqua Warehouse Groups Marketing Officer - overseeing all things news worthy in the hot tub industry, with tips and tricks that are bound to make a splash.

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