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The name muriatic acid means “pertaining to salt.” This name refers to how the chemical composition derives primarily from salt-based compounds.

People add muriatic acid to their pools to keep the pH levels balanced. It’s a highly acidic compound that’s also used for rust removal, cleaning cartridge filters, and removing stains.

It helps lower the pH levels and balance the overall alkalinity levels in the water. If you’re eager to know how to use muriatic acid, how much muriatic acid to add to your pool, and how to protect your skin from burns, keep reading!

Why Should You Use Muriatic Acid in Your Pool? 

Muriatic acid is an effective tool for lowering the alkalinity of your swimming pool. Due to its high acidic levels, it’s far more potent than most mainstream methods of lowering pH. 

Using this acid can help keep your pool’s pH levels balanced long term. While most supply stores sell softer acidic compounds such as sodium bisulfate, this might not be sufficient. 

Sodium bisulfate is safer and easier to use than muriatic acid, but it’s not nearly as potent. Muriatic acid will significantly lower the pH of your pool and create a poor growing environment for algae. 

By creating an environment unwelcoming for plant spores it makes chlorine more potent. This means your water will be less cloudy, helping you achieve crystal-clear water. It also helps cut back on calcium and mineral deposits developing in your pool systems and tiles.

Applying muriatic acid to your pool isn’t very complicated but it’s important to know what you’re doing. Adding too much and using it in high concentrations can damage your pool liner and any metal parts. 

Start by testing the water’s pH levels. If the pH is 7.8 or above, you’ll need to use a higher dose or a more concentrated variety of muriatic acid. 

As a general rule, you’ll need approximately ¼ a gallon of muriatic acid for a 15,000-gallon pool. This is the dosage for muriatic acid with acidity between 15-17%. However, if you’re really struggling to keep your pH lowered, you might consider using muriatic acid with 30% acidity. 

This can be applied directly to the pool, but make sure you wear protective goggles and avoid breathing the fumes. Alternatively, you can dilute the acid in water at a ratio of 1 to 10 before adding it to your pool water. 

Is Muriatic Acid Safe to Use in a Swimming Pool? 

Muriatic acid is safe to use in a swimming pool as long as you use it properly. As a highly corrosive material, it can damage tile and the pool liner if added improperly.

The best way to avoid damaging your liner or other pool parts is to ensure you dilute it before using it. Dilute your muriatic acid in water before adding it to your swimming pool to prevent it from rusting your pool parts.

As long you use it properly, muriatic acid is safe for treating the water in your swimming pool. It’s a more effective agent at lowering the water’s pH than other softer chemicals. It also helps cut down on algae and mold spores that other weaker acids might be unable to cut through.

Is Muriatic Acid Safe for Humans to Use? 

Muriaric acid is safe for human use when handled properly. You should follow certain safety precautions before using it because of its potency.

There are several levels of acidity for muriatic acid. Most compounds rank between 14-32% in intensity, impacting the muriatic acid’s effectiveness and corrosiveness.

Handling this acid is dangerous if you don’t do it correctly. However, it’s not dangerous to your pool or anyone entering the water. Rather, muriatic acid is most dangerous before it’s diluted.

Adding undiluted hydrochloric or muriatic acid can be dangerous for several reasons, including: 

  • Damage your lungs
  • Damage your esophagus 
  • Severe burns
  • Skin irritation
  • Other skin damage
  • Damage the metal parts of your pool
  • Weaken pool liner

Dilution isn’t only important for your health but also for your swimming pool’s well-being. Simply tossing hydrochloric acid or muriatic acid in the pool water is not good. The safest way to use muriatic acid is to mix muriatic acid with water before adding it to your pool water.

If the water’s acidity is too high, it can cause the metal in your pool to decay and rust prematurely. Thus, following the specific directions on the bottle to balance your swimming pool chemistry is important. 

Some home improvement stores sell this chemical in its raw form, known as hydrochloric acid. While this form of muriatic acid is potent, it’s likely far more powerful than you’ll need for your pool water.

It’s also more caustic and dangerous for human health than muriatic acid. However, both are harmful if they get on your skin or you breathe in the fumes. Always wear protective gear when adding muriatic acid to your pool.

How Do You Properly Dilute Muriatic Acid to Use in a Pool? 

The amount of muriatic acid you add to your pool water depends on your pool’s pH level. We recommend testing your pool water chemistry before adding anything additional to the water. 

Proper swimming pool maintenance includes thorough instructions on balancing your swimming pool water. Pool owners want the ideal pool pH level of approximately 7.2. Improperly balanced water can stain the pool liner and swimming pool tile. 

To properly dilute the muriatic acid before adding it to the swimming pool, follow a 1/10 ratio. This means your mixture should be 1/10 acid and 9/10 water. This may fluctuate depending on how bad the pH levels of your swimming pool are, but it’s a reliable rule of thumb. 

This translates as adding one-tenth the amount of muriatic acid as water. Therefore, if the bucket is five gallons, 0.5 gallons of this bucket should be muriatic acid. 

However, this is only true for muriatic acid, that’s between 14-17% acidity. If it’s higher, you should adjust your measurements to closer to 0.25 gallons per 5 gallons of water. Unless your pH levels are very high, then you’ll want to use a higher concentration of acidity. 

If your pH levels are above 7.8, use higher acidic muriatic acid (closer to 30%) and follow the 1/10 dilution system. This means using 0.5 gallons of muriatic acid per 5 gallons of water. 

Last, never use water with many chemicals in it to dilute muriatic acid, and ensure you add the acid to the water. Never pour water into muriatic acid or hydrochloric acid since it can cause a chemical reaction.

How Do You Store Muriatic Acid? 

Reinforced materials are the best options for storing highly corrosive substances like muriatic acid. These containers can include reinforced plastic, glass, metal, or rubber. Rubber and an acid-resistant plastic container are better choices over metal because they can potentially react to muriatic acid or hydrochloric acid. 

Reinforced fiber containers (fiber-reinforced polymer) make the best muriatic acid bucket. Storing muriatic acid in these containers is considered the safest option since its the least likely to corrode. 

Fiber-reinforced polymers are useful in construction and reinforced storage. It’s one of the few materials that resist wear or erosion from harsh chemicals. 

Other things you must consider for muriatic storage include proper ventilation and a sealed cover. Never leave the container open or in a damp, hot area. 

According to a factsheet from U.C. Davis, muriatic acid is non-flammable. However, it is a reactive chemical compound that can produce a dangerous, toxic gas. Keeping it inside a hot shed with little ventilation can create a hazardous working environment. 

Keeping muriatic acid and hydrochloric acid covered and sealed shut at all times is also very important. Since these acids react to water, it can be dangerous if rainwater or some other water source contaminates it. 

A properly sealed container prevents unwanted water or liquids from spilling into the bin and causing a chemical reaction.

What Else is Muriatic Acid Used For? 

Muriatic acid is a powerful cleaner used in various industrial cleanup projects. It’s a potent solvent that can dissolve salts and other mineral buildups without requiring much physical effort. 

Chemists make muriatic acid by combining different chemicals until they create a reaction. This chemical reaction occurs by adding hydrochloric acid to various solvents, including water. 

As the acid and water break down, they form muriatic acid. The water chemistry reacts with the hydrochloric acid creating a highly corrosive substance. Another name for muriatic acid is “spirits of salt,” owning to how the acids draw out the sodium compounds in the mixture.

When added to materials such as concrete or metal, muriatic acid can dissolve rust and stains. However, when added to a swimming pool, it can also lower the overall pH of the water. The acidity makes the pool water a less ideal environment for algae growth.


Using muriatic acid is an effective way to balance your swimming pool water. It lowers the overall pH of the water and makes it more suitable for swimming. 

A swimming pool with a high pH is more prone to algae and mold development. This is especially true for U.S. regions with hard water and high amounts of dissolved minerals. 

Adding muriatic acid or hydrochloric acid can effectively lower the pH and prevent slimy pool water. We hope this guide helps you reach an optimal swimming experience all year round!

Extra Information on Muriatic Acid FAQ 

Is Muriatic Acid the same thing as Hydrochloric Acid? 

Pure hydrochloric acid is similar to muriatic acid. Both compounds are made from hydrogen chloride and are technically the same. The main difference between muriatic acid and hydrochloric acid is its concentration and clarity.

Both compounds contain HCI molecules, which they share through their unified composition of hydrogen chloride. They’re commonly confused with nitric acid, but these elements are very different chemicals.

Nitric acid is a very strong acid, but it’s composed of several elements not present in hydrochloric acid. Hydrochloric acid contains the molecular structure of HCI, while nitric acid contains HNO3.

What Happens if You Handle Muriatic Acid Improperly? 

One of the main dangers of mishandling muriatic acid is the potential for burns and lung damage. Pool owners must worry about this when adding muriatic acid to their pool water.

Once the acid is in the water, it’s fairly safe. How much muriatic acid you add is also an important thing to consider. You can use muriatic acid directly in the water if you avoid breathing in the fumes.

Otherwise, the acid can damage or harm your throat and lungs. Just remember this is a strong acid and must be handled with the utmost precaution. Otherwise, it can cause permanent damage, especially after prolonged exposure.

Finally, ensure you always store muriatic acid safely in an air-tight container away from sunlight. Breathing these fumes in an enclosed area is dangerous, especially under certain concentrations.

How Long After Adding Muriatic Acid To Water Do You Have To Wait To Swim? 

The waiting period for swimming after treating swimming pools depends on how much muriatic acid you use. However, most home improvement stores sell a slightly diluted version which only requires 15-30 minutes of waiting.

As the pool owner, however, it’s your responsibility to monitor the health of your pool water. Make sure you test it regularly and regulate how much acid you use.

If you have irregularly high alkalinity, you might need to do a few treatments before the pH drops. While high alkalinity isn’t dangerous if you’re using high amounts of acid treatments, you’ll want to be careful before letting people swim.

Can You Dispose of Old Containers at the Local Recycling Center?

Hydrochloric acid and muriatic acid containers must be treated as potentially hazardous waste. Most hazardous materials have a distinctive notice written on the outside warning you about the contents.

Sometimes a local recycling center may accept old containers for muriatic acid. However, this isn’t the case for every state, and you must research how to properly dispose of contaminated containers.

Will Baking Soda Work Against Hydrochloric Acid?

Baking soda is a base, not an acid. As a base, it reacts to other acids in the water and increases the alkalinity levels of water.

Thus, baking soda will interact with hydrochloric acid and disrupt it from lowering the pH levels. Pool owners occasionally add baking soda to their swimming pools when the water becomes too acidic.

You’ll only want to add this if your pool’s acidic levels are too high.