How To Raise Alkalinity In A Hot Tub – Easy Guide

Michael Keenan


Hot Tub Water Chemistry

Are you struggling to maintain the proper alkalinity levels in your hot tub? Low alkalinity can cause a range of issues, from corroding metal components to irritating your skin and eyes. But don’t worry, there’s a simple solution!

In this article, I’ll guide you through the process of increasing the alkalinity in your hot tub, ensuring that it remains balanced and safe for use.

Firstly, let’s understand what total alkalinity is. It refers to the amount of alkaline substances present in the water, which helps stabilize pH levels.

I’ll cover why low alkalinity is a problem and how it affects both your hot tub and your health. Then, I’ll give you step-by-step instructions on how to raise alkalinity in a hot tub – effectively.

Along the way, I’ll discuss the importance of balancing pH levels alongside maintaining proper alkalinity.

By following these tips and techniques, you’ll be able to increase the alkalinity in your hot tub and keep it in optimal condition.

raise alkalinity in hot tub water

Key Takeaways

  • Low alkalinity can lead to corrosion, damage to surfaces, skin irritation, and cloudy water in a hot tub.
  • Regularly testing the water and making necessary adjustments is essential for maintaining proper alkalinity levels.
  • Baking soda and soda ash can be used to increase alkalinity in a hot tub.
  • Balancing pH levels is crucial for maintaining alkalinity and water quality in a hot tub.

This article is part of my series covering everything you need to know about alkalinity in your hot tub. You can also see – how to lower alkalinity in a hot tub. Everything you can possibly need!

What is Total Alkalinity

Now, let’s dive into what total alkalinity is and how you can easily increase it in your hot tub.

Total alkalinity refers to the amount of alkaline substances present in the water. Alkalinity refers to the water’s ability to resist acidification. It acts as a buffer against pH fluctuations, helping to maintain the water’s stability and prevent corrosion or scaling of the hot tub components.

The ideal alkalinity of hot tub water is between 80 and 120 ppm (parts per million). Don’t worry it’s not that complicated – ppm is just the scale of measurement that is used.

By keeping alkalinity within this range, you can ensure that your hot tub water remains balanced, safe, and comfortable for use.

Be sure to test the water regularly using a reliable testing kit to monitor the alkalinity levels and make any necessary adjustments.

By understanding what total alkalinity is and how to increase it properly, you can maintain a healthy and enjoyable hot tub experience for yourself and your guests.

What Causes Alkalinity to Drop in Hot Tub Water?

The alkalinity level in your hot tub can drop due to the use of certain chemicals. Acid-based products like sanitizers and shock treatments can reduce the water’s alkalinity. These chemicals kill bacteria and break down organic matter, but they can also neutralize alkaline substances in the water.

Other things that can lower the water’s alkalinity include heavy rain or a lot of evaporation, which can dilute the water and lessen its mineral content. Also, using high-powered jets for a long time can lead to aeration, which causes carbon dioxide to escape and changes the pH level.

To find out more about what can cause low alkalinity in a hot tub see this guide – it goes into more detail.

Why Low Alkalinity Is a Problem

Having low alkalinity in your spa water can lead to several problems. Alkalinity acts as a buffer, helping to stabilize the pH levels in your hot tub. When alkalinity is too low, the pH levels become unstable, resulting in potential problems such as corrosion of metal parts, damage to surfaces, skin irritation, and cloudy water.

Low alkalinity can make it difficult to maintain proper sanitation levels in your hot tub, increasing the risk of bacterial growth and reducing the effectiveness of chemicals.

It’s important to address low alkalinity quickly to avoid problems getting out of hand. That’s up next.

How To Increase Alkalinity In A Hot Tub

To raise the alkalinity in your hot tub, there are a couple of effective options.

  • Firstly, you can use baking soda. Yip – simple baking soda the common household item!
  • Another option is adding soda ash, a chemical compound specifically designed to raise alkalinity levels in water.

Using Baking Soda

Using baking soda is a fantastic way to quickly boost the alkalinity in your hot tub. It gives you crystal-clear water and a more enjoyable soaking experience. Baking soda, or to give it its proper name – sodium bicarbonate, is a readily available and cheap household product that can be used to increase alkalinity levels.

If you prefer to use baking soda made specifically for hot tubs and spas you can buy it online or from your pool supply store as Alkalinity Increaser or Alkalinity Up. There are several brand names available but they contain simple baking soda!

To increase alkalinity using baking soda:

  1. Test the alkalinity level of your hot tub
  2. Calculate the amount of baking soda needed for the volume of your hot tub
  3. Add the baking soda to a small bucket of water and let it dissolve
  4. Add the mixture to your hot tub and run the pump for twenty minutes
  5. Test your water again and repeat if necessary

Remember you are aiming for alkalinity between 80 and 120 ppm. The baking soda will dissolve quickly and start working immediately to raise alkalinity levels.

Regularly monitoring and adjusting alkalinity levels using baking soda will ensure that your hot tub stays balanced and provides you with an optimal soaking experience every time.

One big advantage of using baking soda to raise alkalinity is that it has little effect on the pH levels.

Adding Soda Ash to Increase Alkalinity

Adding soda ash (sodium carbonate) is another effective way to increase alkalinity in your tub. Soda ash is the active ingredient in several branded alkalinity increasers.

The application is the same as for using baking soda. Test, mix, add, and test again. Easy when you know how! One thing to note is that soda ash can increase the pH levels so you need to test them and adjust as needed.

How To Balance Your pH Level

Increasing alkalinity in a hot tub can lead to an increase in the pH of the water. And you don’t want that! Alkalinity and pH are closely related but they are not the same thing.

pH levels can fluctuate and are easily affected by pollutants or even rain. If you maintain the proper alkalinity level, it reduces the way the pH fluctuates. That’s what people mean when talking about having balanced water.

As I mentioned above, soda ash is more likely to raise the pH but it’s good practice to check the pH after increasing alkalinity. The ideal pH for your hot tub water is between 7.4 – 7.6.

To balance your pH level effectively, start by testing the current pH using test strips or a digital tester. If the pH is too low (below 7.4), add a pH increaser such as sodium bisulfate to raise it to the ideal range of 7.4-7.6.

On the other hand, if the pH is too high (above 7.6), add a pH reducer like muriatic acid to bring it back within the desired range.

It’s important to follow manufacturer instructions and make adjustments gradually, allowing time for proper distribution throughout the water before retesting and readjusting if necessary.

Remember, keeping your hot tub’s pH level and alkalinity balanced will prolong your hot tub equipment lifespan and ensure bather comfort and safety.

Here are five reasons why you want the proper alkalinity levels in your hot tub:

  • Balancing pH levels: Alkalinity acts as a buffer, preventing drastic changes in pH levels and keeping them within the ideal range of 7.4 to 7.6.
  • Reducing corrosion: Increasing alkalinity helps protect your hot tub equipment from corrosion caused by low pH levels.
  • Enhancing water clarity: Alkalinity aids in clarifying the water by neutralizing acidic compounds that can cause cloudiness or discoloration.
  • Preventing skin irritation: Proper alkalinity levels ensure that the water is gentle on your skin, reducing the risk of dryness, itching, or rashes.
  • Extending chemical effectiveness: When alkalinity is balanced, sanitizers like chlorine work more efficiently, ensuring cleaner and safer water for longer periods.

So, maintaining the proper alkalinity levels in your hot tub is worth the effort! It’s easy to keep on top of as part of your weekly maintenance program.

To Sum Up

Maintaining the proper alkalinity in your hot tub is crucial for optimal performance and enjoyment. Low alkalinity can lead to pH fluctuations and other water chemistry issues, affecting the effectiveness of sanitizers and causing discomfort to bathers.

To increase alkalinity, add baking soda or a specialized alkalinity increaser according to the manufacturer’s instructions. Regularly testing and balancing both alkalinity and pH levels will ensure a safe and enjoyable hot tub experience for all.

Thanks for reading!

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years of experience in pool care, plant care, and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!