How to Lower The Alkalinity in Your Hot Tub With Vinegar

Alkalinity plays an essential role in the water balance in the hot tub. A too high alkalinity level is bad for the water quality and equipment. But how can you lower a high alkalinity level with vinegar?

To lower the alkalinity in the hot tub, the first thing to do is start the pump. Then pour 4 cups of vinegar into the hot tub and wait until the agent has circulated. After 1 hours, the alkalinity is tested. If necessary, the process is repeated until the ideal alkalinity of 80 – 120 ppm is reached.

This article will show you how to lower the Alkalinity in the hot tub with vinegar and what to watch out for.

How to reduce the alkalinity in the hot tub with vinegar?

Maintaining the proper alkalinity level in your hot tub is an important element of hot tub care.

The production of white scaling along the tub’s walls is caused by alkalinity and pH that is excessively high.

You can buy goods at a pool supply store to adjust the alkalinity and pH, but if you don’t have these chemicals on hand or prefer a more natural method, you can safely lower the alkalinity by adding vinegar to your spa. 

  1. After a few hours of circulating water, check the pH of the hot tub. The average pH level in a hot tub is about 7.2 to 7.6.
  2. To lower the pH of the water, measure out four cups of vinegar and pour it straight into it. White home vinegar or apple cider vinegar can be used. 
  3. After adding the vinegar, ensure that the acid is properly circulated throughout the water by making sure that the pump is running.
  4. Run the pool pump for 1 hour to allow the waters to re-calibrate.
  5. Test again with the test strips. 
  6. Repeat the process, adding four-cup increments of vinegar to the water until the alkalinity is at the desired level. 

How much vinegar is required to lower the alkalinity in the hot tub?

It is difficult to say exactly how much vinegar you will need to lower the alkalinity in the hot tub.

You have to test your way down slowly because the acidity can vary depending on the vinegar manufacturer of your choice.

Take four cups of vinegar and pour it into the water in your hot tub to lower the alkalinity.

Before you pour in the vinegar, make sure to mix the water in the tub.

Depending on what you have on hand, you can use regular vinegar or apple cider vinegar.

After a few hours, turn off the jets and test the water.

Continue repeating the procedure until you achieve the desired result.

Adequate hot tub maintenance will make your hot tub last longer, and you will be able to sit back, relax, and enjoy the moment in it.

How long does it take to lower alkalinity in a hot tub with vinegar?

Give 1 to 3 hours for the pump to circulate the water before adding vinegar.

The pumps will thoroughly mix the acid with the whole of the water in the hot tub. This is to ensure that the pH and alkalinity remain consistent. 

Test the water’s alkalinity and then the pH after the appropriate period of time has passed.

The alkalinity should already be balanced if the chemical application was successful.

However, the pH level may take a little longer to adjust.

If, after 24 hours, the alkalinity remains too high, repeat the process until both are balanced. 

Is it safe to use vinegar to lower the alkalinity in a hot tub?

The use of vinegar in a hot tub or spa is safe.

White vinegar is an acetic acid solution created from grain and water that can be used for cooking and cleaning.

Cleaning a hot tub with vinegar is safe and effective. On the other hand, a pH decreaser is a more effective way to lower the alkalinity in a hot tub.

The active element in pH decreasers (sodium bisulfate) lowers total alkalinity, sometimes to the point where you’ll need to re-adjust your total alkalinity. 

Sodium bisulfate also helps to stabilize pH, so if you need to adjust your total alkalinity, it will be less of a pH rollercoaster. 

Muriatic acid is another option for lowering pH and alkalinity in a hot tub.

Working muriatic acid necessitates using safety glasses, chemical-resistant gloves, and a great deal of caution due to its acidic nature.

You can choose a less acidic muriatic acid substitute product to be even safer.

However, you’ll still need to put on your safety gear. 

Also, note that pouring muriatic acid directly into your hot tub is not a good idea.

You’ll need to dilute it before adding it to your hot tub and aerating it with the jets.

Finally, evaluate the water after allowing it to circulate overnight.

What causes alkalinity to go up in a hot tub?

To be honest, high alkalinity in hot tubs isn’t a common problem.

Most owners empty and clean their hot tub every 3-4 months to keep unwanted materials from piling up. 

However, there are a few significant sources of high alkalinity in a hot tub: 

  • Too Many Chemicals: If you add too many chemicals to your hot tub, your TDS (Total Dissolved Solids) will rise. Drain and clean your hot tub every 3-4 months to avoid this problem. 
  • Colloidal Particles: All of your body lotions, sunblocks, perfumes, hair gel, sweat, and other gross body stuff could be raising the pH and alkalinity level in the hot tub. Therefore, before you go in your hot tub, take a shower! 
  • Your Water Supply: You may live in an area where the alkalinity of your local water supply is high. In this instance, request a water reading from your township, county, or municipal water district.
  • Human Error: You may have accidentally used too much alkalinity increaser or baking soda to raise the alkalinity in the hot tub.

A high alkalinity level in your hot tub needs to be reduced to avoid other problems with the water.

In this case, some guides recommend vinegar. 

But can you use vinegar to lower the alkalinity in a hot tub?

Although vinegar can reduce alkalinity in a hot tub, introducing a pH decreaser is the simplest way to do it (sodium bisulfate). 

Signs of high alkalinity in hot tubs

The way your hot tub runs may typically tell you if the pH and alkalinity are too high.

Chlorine-based disinfectants are less effective when the alkalinity and pH are too high.

As a result, the water quality in the hot tub degrades, producing build-up and other issues. 

The following are symptoms of high alkalinity and pH in the hot tub water: 

  • The formation of scales on the tub’s sides and bottom. 
  • Cloudy water in the hot tub.
  • Inflammation of the skin.
  • Itchy eyes when you use the hot tub.
  • Inadequate sanitary conditions.
  • The filter’s life expectancy will likewise be reduced.

The pH and alkalinity are definitely too low if you detect corrosion, etched plaster, or discolored plaster.

Low alkalinity is frequently attended by rapid fluctuations in pH.

Negative effects of high alkalinity in hot tubs

When the alkalinity of your hot tub is too high, the basic (alkaline pH level) conditions can lead to a number of issues, including:

Swimmer Issues:

  • Swimming in a hot tub with high alkalinity and pH can irritate your skin, eyes, and nasal passage. 

Issues with the hot tub:

  • A high pH in a pool can result in scale, clogged filters, decreased chlorine effectiveness, cloudy water, and algae growth. 
  • Pools with high alkalinity can cause pipe scaling, which can obstruct water flow. When the water flow is blocked and not optimal, your pump is put under additional strain. 
  • A clogged pool filter is another side effect of a high alkalinity in your hot tub. A blocked filter can obstruct water circulation once more and may shorten the life of your pump by forcing it to work harder. 

Conclusion on using vinegar to lower the alkalinity in a hot tub

Allow at least 30 minutes for the water to circulate after adding vinegar to your hot tub before retesting.

Alternatively, retest the next day for more precise results. 

You can maintain the alkalinity between 80 and 120 ppm, but some guides also prefer the alkalinity at 100-150 ppm. You should test what works best in your hot tub!

Do you have any further questions on how to use vinegar in your hot tub to lower the alkalinity?

Contact me at @contactswimfool on Twitter, Facebook, YouTube, or Pinterest – I’ll be happy to help.

Have fun lowering the alkalinity in the hot tub!

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Hi. I'm Max Berg. I've been in the pool industry since 2015 and have always felt drawn to water. I'm the author behind, where I share my years of experience in pool maintenance and give helpful tips on keeping a swimming pool or hot tub clean. My tips reduce the costs of water treatment and protect the environment.

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