How to Lower Alkalinity in Your Hot Tub

Closed hot tub in a backyard during the spring

Alkalinity is often confusing for new and veteran hot tub owners alike. While it is similar to alkaline on the pH scale, it’s not quite the same. And, while some people tolerate high alkalinity in their hot tub routinely, it really isn’t good for your hot tub or yourself. Here’s an explanation of exactly what alkalinity is and how you can lower yours if it is too high.

What is Alkalinity?

When you test your water, you usually test for at least two things: hot tub pH and alkalinity. The pH scale is a measurement of how basic or acidic something is. Your water needs to be at the right pH to be comfortable and safe.

Alkalinity is closely related to the pH scale. It is a measurement of how many basic substances are in your water. As basic is also called alkaline, alkalinity is a measurement of how many alkaline substances are in the water. But it is not a measurement of how basic or alkaline the water itself is.

There may be many alkaline substances in your water, including cyanurates, hydroxides, carbonates and bicarbonates. It’s true that having more of these will make your water more alkaline. The measurements are usually closely related. However, there are circumstances where your hot tub pH and your alkalinity will be out of sync, so measuring both is important.

If you are unsure of your water’s alkalinity levels, it may be time to have it tested. At Oakville Home Leisure we can test your hot tub water. Come visit us today.

Why Does Alkalinity Matter?

It’s vital to keep your hot tub’s pH at the right level. Slightly more basic water will help chlorine, or bromine, work better. However, pH is a very sensitive thing. It is easy for the water to become too acidic. Having the right amount of basic substances in the water will protect your hot tub from swinging towards acidity too quickly. The alkaline substances are like sandbags on a hot air balloon, keeping it from going to high.

Ideally, the alkalinity of your tub should be between 80 and 120 ppm, or parts per million.

Open Hot Tub looking over green landscaping in the Summer

What if My Alkalinity is too High?

Typically, we worry about alkalinity levels that are too low, as this can make the hot tub unsafe and uncomfortable. While it is rare to have alkalinity that’s too high, it can happen. When it does, your water pH may become too basic or too alkaline. Then, you may see the water go cloudy, the water may burn your eyes or skin, and the hot tub itself may suffer scaling.

In order to correct this problem, you’ll need to add an acid to the hot tub. Specifically, muriatic acid or sodium bisulphate should work. Be sure to buy chemicals meant for hot tub use and follow the directions carefully.

Keeping your hot tub balanced is our priority. Whether you need your water to be tested, the correct chemicals or someone to walk you through the process our experts are here for you. Contact us today.

Sources:

https://www.thesundancespastore.com/blog/id/147/title/hot-tub-water-care-what-is-alkalinity

https://www.frogproducts.com/total-alkalinity-spa/