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How To Lower Alkalinity In A Hot Tub

How To Lower Alkalinity In A Hot Tub

Maintaining the perfect balance of your hot tub water’s chemistry is not just about ensuring a comfortable and safe soaking experience; it’s also crucial for the longevity of your hot tub. One of the key aspects of water balance is managing the total alkalinity. High alkalinity can lead to cloudy water and scaling and even affect your sanitizer’s efficiency. Here’s a step-by-step guide to lowering the alkalinity in your hot tub efficiently and safely.

What is alkalinity, and Why does it matter?

The measure of total alkalinity in water refers to the water’s ability to neutralize acids, which is an essential part of balancing pH levels. This ability is sometimes also referred to as buffer capacity. Now, knowing that is all and good, but why does it matter: Balanced alkaline levels are very important for your health and the health of your hot tub. Unchecked low alkalinity levels can result in green water, erratic pH levels, and high acidity. And those effects can cause corrosion of the surface of your hot tub, strip away the natural oils from your skin, causing dry skin, and corrosion of the internal components of your hot tub.

A high alkalinity level can also cause green water; nobody wants to get into a green hot tub. High alkalinity can also cause very high pH, which can result in calcium buildup or scaling; you might be used to this in your kettle when used for a long time. Calcium buildup can show as yellowish flakes, which are unappealing to the eyes and can clog up jets and damage equipment if they are not dealt with. Lastly, high alkalinity can cause your sanitizer to not function properly as it is designed to be used in water with a balanced alkaline level.

A backyard hot tub with chemicals beside it

As you can see, alkalinity balance is essential for your health and your hot tub’s health, but how do you lower that alkalinity if it’s too high? Here are some simple steps on how to lower your alkalinity levels.

Step 1: Testing The Water

Start with testing the water using a reliable test strip or a liquid test kit. Accurate readings are crucial for determining how much alkalinity decreaser you’ll need to use.

Step 2: Turn Off The Hot Tub

Ensure your safety and the effectiveness of the treatment by turning off the hot tub before adding any chemicals.

Step 3: Choosing The Right Chemicals

Alkalinity can be reduced using a hot tub-specific alkalinity decreaser, commonly found in the form of muriatic acid or sodium bisulfate. These are often available at pool supply stores or online.

Step 4: Application Process

After turning off your hot tub to halt water circulation, carefully add the decreaser following the manufacturer’s guidelines. The amount needed will depend on your hot tub’s volume and the current alkalinity level. Distribute the decreaser evenly in the deepest part of the hot tub.

Step 5: Waiting Game

Once the chemical is added, wait for about 30 minutes to an hour to let it disperse properly. During this period, keep the hot tub off to prevent disturbance in the water.

Step 6: Circulation

Turn your hot tub back on to circulate the water. This helps in evenly distributing the chemicals throughout the tub.

Step 7: Re-testing

After a few hours, test the water again. If the alkalinity is still higher than desired, repeat the process, but ensure not to overdo it as drastically lowering alkalinity can lead to corrosive water.

Step 8: Balancing pH

Lowering alkalinity can also affect the pH levels. After adjusting alkalinity, always check and adjust the pH level to maintain it within the ideal range of 7.4 to 7.6.

Step 9: Regular Maintenance

Regular testing and adjustment of your hot tub water are essential. Keep a consistent schedule to ensure your hot tub’s water stays balanced and ready for use.

Safety Note

Always handle chemicals with care. Use protective gear like gloves and goggles, and follow all safety instructions on the product labels.Β 

A man by a hot reading the instructions how how to use the chemicals safely


“Here’s How To Lower The Alkalinity In A Hot Tub” By Elizabeth Heath From Family Handyman