Homeowners typically pay between $525 and $1,775 to acid wash a concrete or gunite pool, or $0.53 per square foot. Total costs vary significantly depending on the pool size and the pool service company. For example, acid washing a small pool measuring 240 square feet can cost as low as $127.
Acid washing is a process in which muriatic acid, also known as hydrochloric acid, is combined with water to remove any type of stain, mold, and calcium deposits. Acid washing is necessary to maintain concrete/gunite pools, and is generally required every 3 to 5 years. It is important to note that this type of maintenance is not an option for vinyl liner and fiberglass pools.
- What is Acid Washing?
- Average Cost of Acid Washing a Pool
- Cost Estimator by Pool Size
- Related Services
- Pro Cost vs. DIY Cost
- Cost Estimator by Location
- FAQ About Acid Washing
- Find a Pool Service Professional Near You
What is Acid Washing?
Acid washing is a unique cleaning process for concrete/gunite pools that can remove magnesium stains, copper stains, algae, mold, and hard water stains from calcium buildup. Muriatic acid is the essential component for this type of pool cleaning. It helps lower high alkalinity and balance pH levels in your pool water, triggering the chemical reaction and stain elimination.
Here are the steps most pool cleanup services take for acid washing:
- Drain your pool
- Apply special treatment on the edges to prevent the acid mixture from removing too much of the pool plaster
- Perform acid wash
- Once completed, apply final chemicals to make it safe for swimming
- Refill water to the appropriate level
Average Cost of Acid Washing a Pool
| Typical Range | $525 to $1,775 |
| Average Cost Per Square Foot | $0.53 |
Acid washing a swimming pool typically costs between $525 and $1,775 on average, or $0.53 per square foot. Several factors affect costs, including the pool’s size and location. Acid washing is required only with in-ground pools made of gunite or concrete, and is not needed as regularly as basic pool maintenance.
Cost Estimator by Pool Size
Hiring a professional cleanup service to acid wash your pool costs an average of $0.53 per square foot. Similar to installing a new pool or providing basic maintenance, acid washing costs higher as the pool’s size increases. Despite that, costs may still vary depending on the pool company or independent pool cleaners.
| Pool size | Square footage | Average cost |
| 10 x 20 | 200 | $106 |
| 12 x 20 | 240 | $127 |
| 10 x 30 | 300 | $159 |
| 14 x 28 | 392 | $208 |
| 15 x 30 | 450 | $239 |
| 16 x 32 | 512 | $271 |
| 18 x 36 | 648 | $343 |
| 20 x 40 | 800 | $424 |
Related Services
In addition to maintaining your concrete pool, there are several additional services you can consider to spruce up your backyard and upgrade your pool system.
These services include:
Pool replastering
Replastering a concrete or gunite pool’s surface is required when it feels rough or appears to be chipping. This process can give your pool a shiny look, make the surface feel gentler on the skin, and keep the water from draining out.
The typical price range for replastering a pool is approximately $2,500 to $13,000, depending on your pool’s depth and size.
Closing and opening a pool
If your home is in an area prone to harsh weather conditions, you should close your pool during the winter and lower the water level. Once the warmer months arrive, you can open your pool and start using it again.
On average, the process of opening and closing a pool costs $405.
Pool accessories and add-ons
There are plenty of accessories that can help you get the most out of your concrete pool, such as a pool heater and automatic cleaner.
| Accessory | Average cost |
| Pool heater | $1,718-$4,426 |
| Pool filter | $500 to $2,000 |
| Automatic cleaner | $625 |
| Pool deck | $3,600 to $15,733 |
| Pool lighting | $200 to $500 per fixture |
Landscaping
It is necessary to maintain your swimming pool, but upgrading your landscape is a great way to improve your backyard’s visual appeal. There are plenty of landscaping services to choose from, depending on your budget and pool area.
| Landscaping service | Typical price range |
| Artificial grass | $5.50 – $19.75 per square foot |
| Planting flower beds | $650 – $3,000 per flower bed |
| Tree planting | $25 – $3,000 per tree |
| Pond installation | $1,900 – $6,500 |
| Misting system installation | $1,800 – $3,400 |
| Retaining wall | $3,600 – $9,500 |
| Sod installation | $0.90 – $1.80 per square foot |
Pro Cost vs. DIY Cost
Fortunately for pool owners, there is a way to save money and perform this type of wash without the use of harmful pool chemicals.
No-drain acid washing is a fairly safe process that cleans the plaster without draining the pool water. With the proper equipment, it can be a DIY project.
| Equipment | Average cost |
| Pool brush | $20 |
| Water test strips for pH levels | $17 |
But how is no-drain acid washing done?
- Add pH decreaser such as sodium bisulfate
- Pool water’s pH level gets reduced to an acidic level of approximately 1.0, with an alkalinity level close to 0
- Pool is then brushed several times to loosen dirt and remove stains
Overall, this method obtains good results but is not as effective as regular washing with an acid solution.
Cost Estimator by Location
In the case of acid washing, your location is just as important as your pool size. Generally, acid washing in warm climates such as Arizona will cost less than colder climates such as New Jersey. Harsh weather conditions can make cleaning any type of pool more difficult. Areas with decent temperatures throughout the year can simplify the acid washing process.
The table below lists the cost of acid washing from least to most expensive across different states in the U.S.
| State | Average price per square foot |
| Florida | $0.49 |
| Arizona | $0.51 |
| Seattle | $0.52 |
| Texas | $0.53 |
| New York | $0.64 |
FAQ About Acid Washing
Cleaning a concrete or gunite pool with a solution of water and muriatic acid is a dangerous task that, if performed by non-professionals with little experience, can be severely harmful. The cleaning solution can harm your skin and damage other areas of your pool, so this task should only be performed by professional pool cleaners.
• Shortens lifespan of plaster finishes
• Surface may become rough
• Some areas on your pool may become discolored
• Residual acid left in lines or equipment may cause other stains to appear
• Dangerous to the environment, highly corrosive
• Mechanical cleaning, such as sand blasting
• Phosphoric acid: less risky than muriatic acid, and readily available
• Use a pumice stone. You can use it to rub off stains and calcium deposits
Why It’s Best to Hire a Pool Services Professional
Pros typically charge between $525 and $1,775 for acid washing a pool, a process required every 3 to 5 years. Your pool’s size and your home’s location can affect the total amount spent on acid washing, with pool companies also playing a role in the price variations.
Get stains and all of that stubborn algae off your pool walls by contacting a professional pool company in your area.
Note: PoolGnome may get a referral fee for matching you with contractors in your area.
Main Photo Credit: LPETTET / Canva Pro / License
