How Much Does It Cost to Have a Pool Acid Washed?

Maintaining a sparkling clean swimming pool is essential not only for aesthetic appeal but also for safety and longevity. Over time, even the best-maintained pools can develop stubborn stains, mineral buildup, or a dull appearance on the plaster surface. One of the most effective deep-cleaning methods available is acid washing. This process can restore the look of your pool and help extend the life of your surface by removing contaminants embedded in the plaster.

But how much does it cost to have a pool acid washed? In this comprehensive guide, we’ll explore the ins and outs of pool acid washing—its benefits, the process involved, factors influencing the cost, and average prices across the United States. Whether you’re a homeowner considering your maintenance options or a pool professional expanding your knowledge, this detailed resource will serve as a valuable reference.

Table of Contents

What Is an Acid Wash?

Before diving into costs, it’s important to understand what an acid wash entails. An acid wash is a procedure where a diluted hydrochloric acid (also known as muriatic acid) solution is applied to the interior surface of a plaster (gunite or marcite) swimming pool. The acid eats away a thin layer of the plaster, removing surface stains, algae buildup, calcium deposits, and other contaminants.

It’s crucial to clarify that this process is not a routine cleaning method. Unlike regular brushing and sanitizing, an acid wash is a one-time, intensive cleaning that should only be performed when absolutely necessary. Done correctly by a professional, it can rejuvenate your pool’s surface. However, due to its aggressive nature, it can also cause damage if not handled properly.

Why Is Acid Washing Necessary?

An acid wash becomes essential when traditional pool cleaning methods fail. Common reasons for needing an acid wash include:

Heavy staining from algae, metals, or organic materials
Calcium scaling or white, chalky buildup on pool walls
General dullness and discoloration of the plaster surface
Habitual high mineral content in water supply leading to stubborn deposits

This procedure is particularly popular in areas with hard water and in older pools where the plaster surface has significantly deteriorated from years of use and chemical exposure.

How Is an Acid Wash Performed?

Acid washing is not a do-it-yourself process. Due to the corrosive nature of muriatic acid, it requires specialized knowledge, equipment, and safety precautions. The process generally involves the following steps:

Draining the Pool: The water is completely or partially drained, depending on what’s needed. Some acid washing techniques, like “bathing,” involve leaving a layer of water on the bottom to neutralize falling acid.
Application of the Acid Solution: Professionals dilute muriatic acid with water and apply it manually using brushes or spray equipment.
Scrubbing and Monitoring: The acid is scrubbed gently to break down stains and deposits. Technicians must monitor the process closely to avoid over-acid exposure, which can etch or damage the plaster.
Neutralization: Once the acid has done its job, the surface is neutralized using an alkaline solution, often soda ash (sodium carbonate) mixed with water.
Rinsing and Disposal: Intensive rinsing follows, ensuring all traces of acid are removed. Wastewater from acid washing is highly acidic and must be responsibly disposed of to avoid environmental harm.
Refilling and Rebalancing: The pool is refilled and chemicals are adjusted to bring pH, alkalinity, and sanitizer levels back to balanced pool conditions.

Equipment and Safety Considerations

Safety is paramount in this process. Professionals wear personal protective equipment (PPE) such as gloves, goggles, and acid-resistant clothing. Pool acid washing also requires proper ventilation and precautions to avoid chemical fumes.

How Much Does a Pool Acid Wash Cost?

To answer the central question: the cost of an acid wash can vary widely depending on several key factors such as the size of your pool, accessibility, extent of contamination, and geographic location. On average, most homeowners in the U.S. typically pay between $1,000 and $4,000 for a standard pool acid wash job.

Factors That Influence the Cost

Let’s break down the primary elements that affect the price:

1. Pool Size

The size of the pool is the most significant determinant of cost. Larger pools require more labor, more chemicals, and more safety measures due to their greater surface area. Here’s a general estimate based on pool size:

Pool Size	Estimated Acid Wash Cost
Small (up to 12,000 gallons)	$1,000 – $1,800
Medium (12,001 – 20,000 gallons)	$1,800 – $2,500
Large (20,001+ gallons)	$2,500 – $4,000+

2. Condition of the Pool

The more heavily stained or calcified your pool is, the more intensive the acid washing process will be. If multiple applications or additional manual scrubbing are required—as in the case of persistent metal stains or thick calcium scaling—the cost will typically increase accordingly.

3. Local Labor Rates

Pool professionals charge based on the local economy. For instance, labor rates in Southern California, South Florida, and Arizona—where many pools exist—are generally higher than in the Midwest or Southeast. Urban areas command higher rates due to increased overhead for pool service companies.

4. Accessibility and Drainage Conditions

If the area around the pool is cluttered, tight, or difficult to access, additional labor time and effort may be needed. Drainage options also matter. Some localities have strict water disposal regulations for acid-contaminated waste, requiring licensed draining or sewer hookups which can affect the final price.

5. Additional Services

Many pool service companies offer acid washing as part of a comprehensive resurfacing or renovation package. In some cases, if tile cleaning, waterline replacement, plaster touching-up, or new coping installation are included, the cost increases. Even small supplementary services like filter cleaning or equipment inspection can add a few hundred dollars.

What to Expect During an Acid Wash?

Knowing what happens during the process gives homeowners an idea of what they are paying for and helps in identifying quality service.

Day 1: Preparation

On the first day, the pool is prepared by:

Removing ladders, lights, and accessories.
Draining the pool, which may take 8–12 hours depending on pump size and drainage capacity.
Protecting nearby plants and surfaces from acid spills.

Day 2: Application and Reaction

The actual acid application and scrubbing occurs here. Acid is applied, given time to react, scrubbed, and immediately neutralized. This is the most skill-dependent part of the service, and it usually happens under the supervision of a licensed technician.

Day 3: Rinsing, Refilling, and Chemistry Adjustment

On the last day:

Thorough rinsing of all surfaces to ensure acid removal.
Refilling the pool with fresh water.
Adding start-up chemicals to establish a safe, balanced water chemistry.

Pros and Cons of Acid Washing

Like any pool maintenance method, acid washing comes with its share of advantages and disadvantages.

Pros

Effective stain removal: Removes embedded stains that can’t be eliminated with regular cleaning or shocking.
Restores surface clarity: Brings back a clean, vibrant look to the plaster.
Resolves scaling: Calcium buildup is cleaned away, improving aesthetics and reducing wear on filtration systems.
Cost-efficient over replacement: Often cheaper than re-plastering the entire pool.

Cons

Risk of damage: Over-application can cause permanent etching or thinning of the plaster.
Time-consuming: Entire process typically takes 2–3 days and leaves the pool unusable during that time.
Environmental concerns: Improper disposal of acid wash water can harm lawns, sewage systems, and wildlife.
May not be a long-term fix: The effects can diminish rapidly without proper post-treatment pool maintenance.

When Is an Acid Wash Not the Best Solution?

Though acid washing provides dramatic results, it’s not a one-size-fits-all option. Homeowners should consider alternatives in certain conditions.

Very old plaster: If your pool’s surface is more than 7–9 years old and needs consistent acid washes, consider new plaster installation.
Frequent acid washes: Professional pool experts recommend not doing this more than once every 5–7 years.
Tile or vinyl pools: Acid washing is not recommended for tile, glass, or vinyl surfaces, as it can damage the materials.
Minor staining: If the problem is localized or minor, alternative treatments like enzymes or sequestering agents can be more appropriate.

Pool Acid Wash Alternatives

If acid washing is a bit too extreme for the issue at hand, homeowners and pool professionals have alternatives:

Phosphoric acid-based stain treatments: Less aggressive and safer for minor staining.
Sequestering agents: Chemicals that bind to metals to prevent staining and discoloration.
Robotic pool scrubbers: Automated devices equipped to scrub calcium and algae spots in plastered areas.
Plaster restoration & patching: For pools with both staining and structural issues.

These options may cost between $200 and $1,200, depending on the scope of the problem and desired outcome.

When Should You Consider an Acid Wash?

Knowing when to call for an acid wash helps you avoid unnecessary procedures or costly mistakes. Consider an acid wash if:

Your pool has not been acid washed in 5–7 years.
You’ve tried traditional stain treatments with no success.
There is a heavy layer of calcium or mineral deposits on the surface.
Post-renovation or post-winter startup, if your pool has visible staining or algae.

Always have a professional inspection before deciding on acid washing—some problems can be solved more affordably using targeted chemical cleaning strategies.

How to Choose the Right Professional for Your Acid Wash

Since this is a major procedure, picking the right company is crucial. Consider the following factors:

Licensing and insurance: Ensure your contractor has the appropriate credentials for handling corrosive materials.
Experience: Ask how long they’ve been performing acid washes and if they have references.
Transparency: The company should clearly explain the process, pricing structure, and any risks involved.
Reviews and ratings: Check local listings on Google, Yelp, or Angie’s List for positive feedback.

Questions to Ask a Service Provider

Before hiring a company:

Do you offer a complete breakdown of charges beyond the acid wash itself?
Will you provide safety precautions for nearby areas during the process?
Will you test the pH after chemical adjustment so the water is ready for use?
Do you have a solution in case something goes wrong with the chemical exposure?

A reputable pool professional should provide honest, detailed answers to all of these questions.

Comparing Acid Wash to Plastering

If you’re facing widespread wear or deep discoloration, it may be beneficial to compare acid washing to total pool replastering.

Price Comparison

While acid washing can provide short-term cosmetic relief, it does not address structural plaster issues. If cracks, significant scaling, or plaster delamination are present, replastering becomes a more permanent—and sometimes necessary—investment.

Maintaining a Clean Pool: Minimizing the Need for Acid Washing

The best way to reduce the cost and frequency of acid washing is through regular maintenance and timely chemical adjustments. Here are a few best practices:

Balance water chemistry weekly: Maintaining pH, total alkalinity, calcium hardness, and stabilizer prolongs plaster life.
Use stain and scale prevention chemicals: These help mitigate discoloration and mineral buildup.
Clean and brush the pool regularly: Physical scrubbing helps remove algae and debris before they become staining agents.
Test source water hardness: Especially if you’re in an area prone to high mineral content, periodic water analysis can be helpful.

By staying ahead of pool chemistry and keeping surfaces clean, many of the problems that lead to acid washing can be minimized altogether.

Final Thoughts: Invest in Quality and Safety

While the cost of acid washing a pool can seem steep, when necessary, it can restore functionality and enhance aesthetics dramatically. Homeowners must be discerning—focus not only on the short-term savings but also on professionalism, safety practices, and long-term maintenance.

Before scheduling the service, be sure to get at least three quotes from licensed service providers. Ask for a custom quote that includes not just the procedure but also cleanup, chemical balancing, and any water disposal fees. By investing in an acid wash wisely, you can continue to enjoy a clean, inviting, and healthy pool for years to come.

Whether you’re in Phoenix, Texas, or Georgia, proper pool care is a long-term commitment—and professional acid washing should be part of a balanced, proactive maintenance approach. Let your pool reflect the care you invest in it.

What is an acid wash for a pool, and why is it necessary?

An acid wash is a process used to clean and restore the surface of a swimming pool by removing built-up stains, mineral deposits, algae, and other contaminants. It involves applying a diluted muriatic acid solution to the pool’s walls and floor, which is then scrubbed and neutralized before draining. This treatment is typically recommended when regular cleaning methods are no longer effective, especially for pools with plaster, cement, or concrete surfaces that have developed discoloration or scaling.

The necessity of an acid wash comes into play when a pool has suffered from long-term neglect, persistent algae growth, or severe staining. It helps rejuvenate the pool’s appearance, improve water quality, and extend the life of the surface. While it is not a routine maintenance task, it can be a critical step in restoring a pool to a clean, safe, and visually appealing condition.

How much does a professional pool acid washing service cost?

The cost of hiring a professional to acid wash a swimming pool typically ranges from $200 to $500, depending on several factors including the size of the pool, its condition, and the region in which you live. Smaller pools with minor staining may fall toward the lower end of the price range, while larger pools that require more labor and materials may cost closer to $500 or more. Some companies may also charge an additional service fee or travel fee depending on location.

The cost also includes the price of the acid, neutralizing agents, and protective equipment used during the process. Professionals will ensure the task is done safely and effectively, which is important given the dangers of handling muriatic acid. In many cases, the price also includes draining and refilling the pool with fresh water, although this can significantly increase the total depending on local water rates.

Can I acid wash my pool myself to save money?

Yes, it is possible to acid wash your pool as a DIY project and save on labor costs, which can bring the overall expense down to approximately $50–$100 for materials. However, this approach requires caution, as muriatic acid is a strong chemical that can cause harm if not handled properly. You must wear protective gear, including gloves, goggles, and long-sleeved clothing, and follow safety procedures carefully to avoid injury or damage to the pool surface.

DIY acid washing is best suited for those with some pool maintenance experience and the ability to follow technical instructions. Mistakes—such as not properly diluting the acid or failing to neutralize it after application—can lead to etching, cloudy water, or damage to pool equipment. Therefore, while doing it yourself can save money, it’s important to weigh the risks and consider hiring a professional if you’re unsure of the process.

How often should a pool be acid washed?

Acid washing is not a routine maintenance task and should only be done when necessary to avoid damaging the pool surface. Most pool experts recommend acid washing every 5 to 7 years, depending on how well the pool is maintained and the water chemistry. Pools in areas with hard water or high mineral content may require it more often, especially if scaling and staining become problematic.

Over-acid washing can wear away the top layer of plaster or concrete, reducing the longevity of your pool’s finish and potentially causing costly repairs. Instead of frequent acid washing, regular brushing, proper chemical balance, and routine cleaning are more sustainable for keeping your pool in good condition. When staining or scaling does occur, alternative cleaning methods like using a stain remover or scaling tool may be sufficient before resorting to an acid wash.

What factors influence the cost of acid washing a pool?

Several key factors influence the total cost of acid washing a pool. The most important is the size of the pool—larger pools require more time and a greater volume of acid and neutralizing agents, which drives up the price. Another factor is the condition of the pool surface; pools with severe staining, heavy calcium buildup, or algae growth may take longer to treat, increasing labor costs.

The location of the property can also affect pricing due to regional differences in labor rates and water disposal regulations. If the pool needs to be drained and refilled, water costs and sewer fees may add significantly to the total expense. Additionally, some pools may require multiple treatments or extra cleaning steps, which can affect both time and material costs. These variables mean it’s best to get a professional estimate tailored to your specific situation.

What is involved in the acid washing process?

The acid washing process typically begins with draining the pool completely so the surface can be treated effectively. Next, the technician will scrub the interior surfaces to loosen dirt and algae before applying a diluted muriatic acid solution. As the acid reacts with the pool surface, it dissolves mineral deposits, stains, and other buildup, restoring the finish. The technician will use brushes and scrubbing tools to agitate the acid and ensure even coverage.

Once the acid has done its job, it must be neutralized using a base solution—commonly soda ash or baking soda—to prevent damage to the plumbing and surrounding environment. The neutralized mixture is then flushed away using a sump pump or similar method. After the cleaning is complete, the pool must be thoroughly rinsed and inspected before being refilled with fresh water. Proper chemical balancing and filtration is required afterward to ensure the pool is safe for swimming.

Are there alternatives to acid washing a pool?

Yes, there are several alternatives that can help address common issues like stains, scaling, and cloudy water without resorting to an acid wash. Non-acid-based stain removers, calcium scale dissolvers, and chelating agents can often resolve discoloration and mineral buildup if used correctly and regularly. Additionally, deep brushing and shocking the pool with a strong chlorine or non-chlorine shock can eliminate stubborn algae without damaging the surface.

If the stains are metallic in nature, a metal sequestrant or water clarifier might be a safer and gentler option. Maintaining proper pH and alkalinity levels in your pool water also helps prevent the formation of scale and staining. Before deciding on an acid wash, it’s often wise to test alternative cleaning methods, which are less invasive, more affordable, and safer for both the surface and the pool owner.