Muriatic Acid For Pools – Everything You Need To Know

Last Updated on October 19, 2021

Pool ownership is much more complicated than you might think it is. It’s not enough for you to just add chlorine and let your pool pump and filtration system do the rest. The truth is maintaining your pool is a complex process, and sometimes you need to know the importance of muriatic acid for pools in your maintenance routine.

Muriatic acid helps in balancing the water chemistry in your pool. The acidity and alkalinity of the water in your swimming pool can easily change due to weather, high water temperature, and by addition of chlorine or other pool chemicals.

You might be surprised to know the many uses and benefits of using muriatic acid on pools.

What Is Muriatic Acid?

Muriatic acid is a less-pure version of hydrochloric acid. Both are highly corrosive and can easily dissolve plastics, clothing, and metals. Muriatic acid contains hydrochloric acid concentration levels between 28 to 35 percent and its pH is less than 1.0, making it one of the most acidic substances available today.

You can easily buy muriatic acid at your local home improvement or pool supply store and is widely used in various tasks such as removing rust and stain on concrete surfaces and reducing the pH in your swimming pool.

Muriatic Acid For Pools: Benefits and Uses

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Muriatic acid is widely used in swimming pools since it’s very affordable and has many uses.

For one, it can be used to clean your pool cartridge filter and remove the residue that builds up in there.

You can also use muriatic acid to clean the interior of your swimming pool. You can scrub your pool walls with muriatic acid to remove any stains and algae on them.

Now, muriatic acid is popular among pool owners because it does a terrific job lowering the pH and alkalinity of your pool water. The pH level on your swimming pool should be between 7.2 to 7.8. If it’s higher than 7.8, then you may start noticing calcium buildup, scaling, or cloudy water soon. It may also result in algae blooms if your pH and alkalinity levels stay too high and can damage your pool’s structure and equipment if you won’t do something to lower them.

You may use various pool chemicals to lower the pH and alkalinity of your pool water, but muriatic acid is the cheapest and effective chemical pH reducer out there.

Step-by-Step Guide On How To Add Muriatic Acid To Swimming Pools

Muriatic acid can be added to your pool directly to lower the alkalinity and pH levels. Here’s our guide on how to add muriatic acid to pools properly and safely.

1. Test your water chemistry

The first thing you should do before adding muriatic acid to your pool is to test your water chemistry levels. While test strips can identify the pH levels of your pool water, we highly suggest using a more accurate testing solution like the pHin Smart Water Care Monitor for Pools.

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  • POOL AND HOT TUB CARE SIMPLIFIED: Instead of showing you continuously changing raw readings, pHin’s built-in intelligence samples your water chemistry more than 1000 times per week and creates...
  • SUPPORTS ALL WATER TYPES: Works with chlorine, bromine and salt water based pools, hot tubs and swim spas.

The ideal readings for the pH level of your pool water should be between 7.2-7.8, which means anything higher than that makes your water too basic.

2. Wear your safety gear

Before you add muriatic acid to your swimming pool, you must wear protective gear to avoid getting your skin burned. Muriatic acid is a very strong acid, and it can easily deteriorate your clothing if you’re not careful and cause extreme burns.

We advise wearing something that can fully cover your arms and legs, and use protective goggles to protect your eyes as well. You should use a pair of gloves that is resistant to acid like these Pacific PPE Chemical Resistant Gloves.

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3. Start diluting the muriatic acid

You cannot add the muriatic acid to your pool without diluting it first, it will certainly cause more problems and may even destroy your pool and its equipment. Diluting enables you to get the right chemistry before you add it to your pool water.

To dilute the muriatic acid, you must fill up a 4 to 5 gallon of bucket with clean water, not pool water. Once that’s done, you must add the muriatic carefully and follow the ratio of 1 part acid and 10 parts water.

Never put the muriatic acid first before you add water as this will cause a chemical reaction to occur between the acid and your plastic bucket. Also, avoid adding water to muriatic acid as this may cause it to splash and get in contact with your skin and clothing.

4. Add it to your pool

Once you’re done diluting the muriatic acid, you can start pouring the bucket’s content into the deep end of your pool. Make sure that you have turned on your pool pump before you do this step. The water should be running and circulating well before you add the acid to your swimming pool.

If you have extremely high total alkalinity and pH levels, you can pour it on different parts of your pool.

5. Test your water chemistry again

After adding the acid and waiting for a few hours, you can start testing the water chemistry levels and check your pH level if it decreased.

If it’s still too high, then you should add more muriatic acid to the pool until you reach the ideal pH and alkalinity levels. You can retest the water every 4 hours until you reach the right pH reading which is anywhere between 7.2 and 7.8.

Alternatives For Muriatic Acid On Pools

If you’re too worried about your safety when adding muriatic acid to your pool, then you might consider the following options.

  • Sodium bisulfate
  • Sodium dichlor
  • Pool algaecide

All of those may be the more expensive option compared to muriatic acid but they can also help you balance your pool’s pH and alkalinity levels. Some of them like sodium bisulfate may take more than a day before it can properly balance your water chemistry.

It’s also worth noting that muriatic acid adds no other chemical species to your swimming pool other than ones that are already present and it has no potential long term side-effects.

Final Thoughts

Muriatic acid is considered the best option to lower the pH and alkalinity levels in your swimming pool. When you’re able to properly balance your pool chemistry, you can avoid the need to adjust your alkalinity levels.

You may also make use of muriatic acid to remove algae, dissolve calcium deposits, remove stains, and clean pool walls and floor. It’s great to have this acid on stock, and if you need help in storing pool chemicals, you should check out our post, How To Store Pool Chemicals.

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