Muriatic acid is a strong and corrosive solution that can be used to clean pool items, lower the alkalinity in your pool, or reduce pH levels. It is also known as hydrochloric acid, and it has many other uses outside of pools.
As a swimming pool owner, it is important to safely use muriatic acid in your pool. In this article, we will discuss how muriatic acid works and go into detail about how you should use it in your pool for maximum benefit.
What Is Muriatic Acid?
Muriatic acid is a strong acidic solution that is created by adding water to hydrochloric acid. It can be used in many applications outside of pools, such as food processing plants, chemical labs, or wastewater treatment facilities.
Muriatic acid is a powerful oxidizing agent, which can remove rust, calcium deposits, and scale from metal surfaces. It is also a very effective cleaning agent, which means that it can be used to clean pool items like filters or plaster.
It can also be used as an acidifying agent to lower the alkalinity level in your pool because muriatic acid lowers pH levels when mixed with water. In its pure form, hydrochloric acid has a pH of 1 to 2. Muriatic acid is the result of dilution, usually by 15 to 30 percent so it can lower the alkalinity in your pool by up to 200ppm, which is a significant amount!
What Does Muriatic Acid Do for a Pool?
You should add muriatic acid to your pool when the pH level is higher than 7.8. At this point, the water will be considered too alkaline or too basic. It can also help clean pool items like filters or plaster and remove rust, calcium deposits, and scale from metal surfaces.
Water that is too alkaline causes a variety of problems for pools. One such problem is that the water becomes less effective at reducing chlorine levels, which can cause eye irritation and dry skin in swimmers.
Is Muriatic Acid Safe?
Muriatic acid can be dangerous when it comes into contact with unintended surfaces, like skin or clothing. It can cause burns and even permanent damage to the surface of your pool as well if it is not used properly.
The most common dangers of using muriatic acid are spilling it on unwanted pool surfaces and inhaling fumes from its use. Proper safety precautions should be taken.
If it comes into direct contact with your skin or eyes, it will also cause irritation. That is why it’s recommended to handle with proper rubber gloves and eye protection.
Can Muriatic Acid Be Used in a Saltwater Pool?
No, muriatic acid cannot be used in a saltwater pool. It will cause corrosion in saltwater pools, usually damaging equipment.
How to Use and Add Muriatic Acid to a Pool
Below you’ll find the step-by-step instructions for using muriatic acid in your pool.
Step 1: Collect a Water Sample
Collect a sample of swimming pool water. This can be done with any type of bucket and a long plastic trowel or putty knife that won’t react to the pool’s chemicals, such as those made from PVC, rubber, or nylon.
Step 2: Test Your Pool Levels
Once you have collected the sample, test it with a pool test kit to ensure that the results will produce accurate measurements for acidic and basic chemicals.
If you’re not sure exactly how much to add, consider utilizing a swimming pool calculator.
- Features a photometer which gives you a digital reading of test results.
- Water resistant housing and carrying case provided.
- Tests Free Chlorine, Total Chlorine, Bromine, PH, Alkalinity, Calcium Hardness, and Cyanuric Acid.
- Uses liquid reagents for all test factors except Cyanuric Acid, which uses tablets.
Step 3: Wear Protective Gear
You’ll want to use protective gear when working with muriatic acid, such as a long-sleeve shirt, pants, and gloves, so it covers your hands, arms, and legs. If you come into contact with the chemical, make sure that you immediately run cool water over the area.
- High-grade natural latex possess a excellent chemical resistance and tear resistance
- Ideal thickness provide a fantastic secure protection yet still tactile sensitive
- Only one size - extra large, but its smooth finish provides excellent grip
Step 4: Calculate the Amount of Muriatic Acid You Need
Use the pool test kit to calculate how much muriatic acid will be necessary to lower your pool’s alkalinity.
Step 5: Dilute the Acid
Once you have calculated the amount, use a bucket of non-pool water to mix one-part muriatic acid with nine-parts water.
Step 6: Slowly Add the Muriatic Acid to the Water
Step 7: Rinse Any Items That Come Into Contact With Muriatic Acid
Make sure to rinse anything that comes in contact with the chemical, so they are safe for swimming in after treatment.
Step 8: Check the PH Levels
If the pH levels are not where you would like them to be, use a pool test kit and add more acid until they reach your desired level.
Once the pool is balanced and has its pH level reduced, use your pool vacuum or skimmer basket to remove any excess chemical from the pool’s surface.
When Should Muriatic Acid Be Used in a Pool?
Muriatic acid should be used in a pool when the pool’s alkaline levels are high. It can also be used as a cleaner for pool items or to remove calcium deposits from the tile in your swimming pool. It should only be diluted before use when used for cleaning purposes.
How Long Should I Wait to Swim After Adding Muriatic Acid?
After adding muriatic acid, you should wait to swim for at least 30 minutes. This will allow the acid time to do its magic, lowering the pool’s alkalinity and pH levels.
How Long Does Muriatic Acid Take to Work in a Pool?
It takes about 24 hours for the effect to fully set in – the water becomes noticeably softer and less alkaline due to muriatic acid’s ability to lower pH levels, as well as remove free chlorine from the pool.
Using Muriatic Acid to Clean Pool Items
Muriatic acid can be used to clean pool items. Just be sure to dilute it first. Here are some items you can clean with it:
- Pool Skimmers
- Pool Pumps
- Pool Filters
- Pool pipes and connectors that are used to connect the pump, filter, or other components together
- Filter Cartridge
- Pool Tile
- Pool Salt Cell
- Vacuum Heads
After you’re done cleaning, be sure to thoroughly rinse your pool products and toys with fresh water to remove any excess acid.
Benefits of Using Muriatic Acid As a PH Reducer in a Pool
The benefit of using muriatic acid as a ph reducer is that it will make the pool’s water softer and less alkaline, which is better for your skin.
Muriatic acid can also lower free chlorine levels in a swimming pool to prevent eye irritation or dry skin from chemical exposure. This makes it perfect for use with children who have sensitive skin.
Muriatic acid can also be used to clean other things like pool tiles and pool vacuum heads.
Muriatic Acid FAQ
What Does Muriatic Acid Do for a Pool?
For your pool, muriatic acid will lower the alkalinity levels in pool water, which will help maintain a balance between acid phosphates and alkaline phosphates. This is important because at higher pH values, corrosive chlorine can become ineffective with lower pH values as it starts to break down into saltwater.
What Happens if You Put Too Much Muriatic Acid In the Pool?
If you put too much muriatic acid in your pool, the pH will drop, and you run the risk of frosting your pool’s surface. This will cause a lot of damage and/or problems for your pool. The acid will erode all the plaster from the swimming pool, which can take months to repair! The corrosive nature of muriatic acid will also dissolve any metal fixtures in contact with it
How Much Muriatic Acid Can I Add to My Pool at One Time?
You can add up to five gallons of muriatic acid at one time. In order to lower the pool’s alkalinity, you will need about four ounces per 100 square feet. You’ll want to add this in increments as it is very dangerous and can level your pool surface if added altogether!
Can You Add Muriatic Acid Directly to the Pool?
No, you should only dilute muriatic acid before directly adding it to your pool. This will prevent the muriatic acid from reacting with the pool surface, which can cause both costly damages and safety hazards.
Muriatic Acid vs. Sodium Bisulfate
If you need your pool water balanced more quickly than this, there are other ways of lowering pH via chemicals like sodium bisulfate. However, sodium bisulfate is not advised using these methods because they do not address the root cause of high alkalinity in pool water.
Where Can I Buy Muriatic Acid?
If you aren’t in a rush, you can purchase muriatic acid online. If you need it ASAP, you can purchase muriatic acid from a pool supply store, hardware store, or some grocery stores. This includes Walmart, Lowes, and Home Depot.
Do I Need to Hire a Pool Professional to Use Muriatic Acid?
The pool owners who aren’t comfortable using some test strips to monitor their pool’s ph and water chemistry may want to consider hiring a professional. Using acids like this product can be very dangerous to work with and should be treated as a harsh substance.
The Bottom Line
When you need to lower the alkalinity in your pool water, muriatic acid is one of the easiest and most effective ways. If you don’t want to invest in more expensive solutions like chlorine or bromine, this natural chemical provides an easy fix for your problem. Just be sure that you calculate how much liquid needs to go into the water before adding it!
Muriatic acid can also be used as part of a routine maintenance plan if done correctly. It’s important not only to use enough but also when needed – too often could lead to other problems with pH levels and algae growth. We hope these tips have helped clear up any confusion around using muriatic acid safely.
For over 15 years, Sean Moore has been sharing his love and enthusiasm for swimming pools and hot tubs with everyone he knows. His goal is to help everyday people DIY their maintenance to save money by teaching how to properly take care of your equipment, safely and correctly balance chemicals, and extend the life of your water oasis.
Pricing on this page was last updated on 2023-10-01