How to Acid Wash a Pool

Pool ownership can be a wonderful thing. Relaxing in the calming waters of your home’s swimming pool is an excellent way to lower your stress levels and get a little exercise. But pools can quickly become stained and overridden with harmful bacteria.

When your swimming pool’s surfaces aren’t coming clean, it may be time for an acid wash. Acid washing can help restore your pool’s natural beauty and appeal and destroy stubborn bacteria or algae. Acid washing a pool begins with gathering the right supplies, but you’ll also need to follow a step-by-step process to enjoy the best results.

In this article, I’ll detail the reasons why you may want to acid wash your pool, as well as some safety precautions you need to take. I’ll also list all of the supplies you’ll need to get the job done and reveal a concise step-by-step plan of attack.

If you’ve been wondering how to get your pool back into tip-top condition, you’ve come to the right place. Let’s get started!

Why Acid Wash Your Pool?

Swimming pools require consistent maintenance to remain clean, attractive, and functional. But even the most diligent homeowner can discover darkening stains, spreading algae, or high levels of bacteria in their pool. When these things happen, an acid wash could help.

Returning your pool to pristine condition does require a little bit of work, but the results are often worthwhile. An effective acid wash and cleaning can help keep your backyard looking irresistible.

An irregular maintenance schedule can make your swimming pool a breeding ground for bacteria and aquatic insects, including mosquitoes and water bugs. Dirt, silt, and rotted organic material can begin to corrode your pool, resulting in costly repairs and refurbishments. You can try a lot of different solutions to get it looking good again, but you need to know when to drain your pool and give it a good scrub.

Still, some types of pool materials can degrade when exposed to muriatic acid. If you’re not entirely certain what your pool is made of, now is the time to check and confirm. Concrete and gunite are the only two materials that can safely withstand an acid wash.

Safety Precautions

Before you begin an acid wash, you’ll want to make sure you’ve taken the right safety precautions. Muriatic acid is only slightly less corrosive than hydrochloric acid, so it can easily eat through your clothes and irritate your skin.

Protecting your skin is paramount to staying safe during an acid wash. It’s also imperative to wear eye protection while cleaning and washing your swimming pool. And thick gloves can keep your hands safe from accidental splashes of acid.

When scrubbing your pool with the acid solution, be sure to keep surfaces constantly wet with clean, fresh water. Also, be sure to keep the solution moving toward the drain at all times. Otherwise, you may develop dips and dents in the surface of your pool.

In addition to a handful of safety supplies, you need the tools and equipment necessary to get the acid wash job done. If you don’t own a drainage pump, several garden hoses, or a specialized scrub brush, you’ll likely need to make a quick shopping trip.

Supplies You’ll Need

Before you acid wash your pool, you’ll need to have:

  • Muriatic acid
  • Safe clothing, glasses, gloves, and boots
  • A powerful submersible water pump
  • A long drainage hose
  • An extended garden hose
  • Washing soda
  • Water testing kit
  • Algae brush
  • Acid brush
  • High-pressure spray nozzle

You’ll also want to make sure that you have access to clean running water and a sewer. If your garden hose cannot extend from your water source to your pool, you’ll need to purchase a longer model or an extension hose. Be sure to check your drainage hose to ensure it can reach the nearest sewer opening.

Finally, you’ll likely want to double-check the durability of your safety apparel. If it’s not acid-resistant, it may be worthwhile to invest in gloves, boots, and coveralls that are able to withstand brief contact with corrosive chemicals.

Okay, let’s get to the steps for washing.

Acid Washing a Pool: Step-By-Step

Once you’ve gathered your supplies, it’s time to get started. Be sure that your safety gear is properly secured and positioned, taking special care to protect your skin, lungs, and eyes. Doing so can help protect you from any accidental injury, including fume inhalation or corrosive burns.

When you’re properly attired and ready to get to work, you’ll want to:

  1. Drain the pool completely
  2. Scrub surfaces
  3. Prepare the acid solution
  4. Wet and wash the pool
  5. Rinse all surfaces
  6. Make the wastewater safe
  7. Drain and refill

By following these seven essential steps, you can ensure that your pool’s acid wash goes swimmingly. You’ll also keep groundwater safe while restoring the look and condition of your pool.

While you could choose to tackle this project alone, it may be wise to consult with a professional when draining an inground backyard pool. Hiring a pool maintenance crew to acid wash your pool could help you save money on equipment, ensure that the cleaning goes smoothly, and prevent costly or painful accidents.

For example, the first hurdle you’ll need to overcome is draining. Inground pools have a nasty habit of ‘popping’ upwards and out of the ground when completely drained. The right technique (and timing) is essential for avoiding the issue.

Attempting to re-install a buckled pool is often costly, so it’s vital to prevent your pool from rising up while acid washing it. This can be tricky, especially if you don’t have any previous experience with draining a pool.

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Draining the Pool

Attach the drainage hose to your submersible pump and train it to the closest sewer grate or opening. Then, turn the pump on and lower into the deepest area of your swimming pool. Depending on the size of your pool and the power of your pump, it may take several hours to fully drain your pool.

Try not to begin this step if your area has been experiencing heavy or consistent rain. The differential pressure between the groundwater and the pool water could cause an inground pool to rise up when drained. The result is a costly repair or replacement job.

Once your pool is entirely drained, you can go ahead and begin removing large piles of debris. Taking the time to remove these obvious contaminants can help make the rest of your acid wash far easier and more potent.

Scrubbing Surfaces

Once you’ve successfully drained the pool, you’ll want to begin removing debris from the bottom of the pool. You can get a jump start on stain removal by using an algae brush to remove surface contaminants. Be sure to keep surfaces wet by running small amounts of fresh water into the pool. Yet, you don’t want too much water puddled at the bottom.

You could also use a spray bottle or watering can in lieu of a hose. Still, when working with a large surface area, a hose may be more effective and convenient.

Prepare the Acid Solution

Follow the manufacturer’s instructions when mixing your acid solution. Always use clean water as your solution base and slowly add muriatic acid. Attempting to add water to the acid could result in chemical boiling, an exceptionally dangerous potential reaction.

If you’re uncomfortable handling or combining an acid mixture, you may want to opt for professional assistance. There’s no shame in admitting that you’re unprepared to safely mix chemicals.

Still, if you do feel confident about your chemistry skills (it’s not that difficult, just go slow and be safe), you can go ahead and create your solution. Be sure to use a resin container to hold your mixture. Other types of materials may instantly weaken after coming into contact with muriatic acid. A leaky container is dangerous, even if you’re wearing protective gear.

Scrub and Rinse Surfaces

Keeping your pool’s surfaces wet, go ahead and begin applying the acid solution. You’ll want to apply the acid and wait for approximately one minute. Then, you can begin scrubbing. Follow the manufacturer’s instructions and don’t leave the acid solution on too long.

Use your acid brush to scrub away stains. Be sure to keep clean water running on these stains while you scrub. Though it will likely take a reasonable amount of time, you should take this opportunity to scrub all of the surfaces of your pool with the acid solution. A thorough job will get the best results and prolong the beauty of your pool.

When you’re finished with your scrubbing, go ahead and give all of your surfaces a thorough rinse. Always rinse toward the drain, allowing the wastewater to flow toward the lowest part of your pool.

Make the Wastewater Safe

Before you drain that sudsy acid-water solution into the sewer, you’ll want to make it safe. Pouring such an acidic solution into local sewage systems is incredibly dangerous.

Not only could the solution eat through your drainage hose or pump, but it could also cause significant harm to the environment. Adding washing soda as you rinse can keep your pool’s bottom safe from unwanted corrosion and help keep your community free of waterborne pollutants.

For every gallon of acid you use to clean your pool, be prepared to sprinkle in two pounds of powdery washing soda ash. This ratio should result in a fairly neutral blend.

Drain and Refill

After confirming that the remaining wastewater is neutral and safe to dispose of, you can restart your drainage pumps and hoses. It may be helpful to run clean water into the pool while draining the wastewater. Doing so can help you remove all traces of the acid before refilling the pool.

When you’re confident that all the dirtied, acidic wastewater has been rinsed from your pool surfaces, you can shut off your drainage pump and remove the hose from the pool. You’ll then want to use the garden hose to refill the pool.

As with draining, refilling could take quite a while. Using multiple hoses or water sources could help you reduce the amount of time it takes to refill your pool. Once it’s reached an acceptable level, be sure to add sanitizing chemicals to help your swimming pool reach a safe pH level.

Be sure to replace any pumps or valves before giving yourself a well-deserved pat on the back. And lastly, enjoy your gorgeous, glimmering swimming pool!

Final Thoughts

No matter which route you decide to take (DIY or getting some help from a pool maintenance crew), you’re bound to enjoy the results of a high-quality, stain-removing acid wash. Say goodbye to stubborn stains, algae, and bacteria!

Questions about the process? Shoot me a note, I’ll be happy to help.

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