Does Your Pool Need an Acid Wash?


One of the pool maintenance projects which is bigger on the effort scale is an acid wash. There are several circumstances when it’s smarter to acid wash the pool than it is to let it go. Today, we’re going to talk about some reasons why it might be time to acid wash the pool.

Colder months are the best time to acid wash a pool. Winter is ideal, followed by the very early months of Spring. Talk to your pool pro about the right time to have your pool acid washed.

Draining a pool should never be taken lightly, however, every five to seven years, the water becomes utterly tired and in need of a change. Also, because of our hard water, the water line can develop a white or grey ring over time, making a pool look unsightly.

Other stains can also make an acid wash necessary. After a hard battle with green algae, the pool may benefit from a good, thorough cleaning and water replacement. Some metals in pools can cause rust, such as light fixtures, nails, even metal hair clips.

People ask us about what is generally involved, so today we’re going to present an overview of the acid wash process.


Draining the pool

First, the pool is drained of the old water. Remember, a drained pool makes the drop-off from the coping steep. Falling into an empty pool is much like a fall from a roof, except there is no grass, only plaster.

The old water will be drained, and the sanitary sewer drain is the best option. If you have a septic system, we will not drain the pool into it as it can overflow. Also, be aware that chemicals and other bacteria can contaminate groundwater. So, it’s best to use the sewer drain. Note: Do not forget to turn off the autofill feature if you have one and do the draining yourself. The pool should be completely drained.

The wash itself

The process of acid washing takes a thin layer of plaster off of the sides of the pool, so it shouldn’t be acid washed too frequently. A combination of muriatic acid and water is used to clean the sides and bottom of the pool in small segments, along with plenty of scrubbing to get the last bit of discoloration.

The protective gear worn by the crew is to protect them from burns as a result of the muriatic acid. They will wash and rinse the pool in sections so it will be clean, but not eroded too deeply by the acid wash.

Soda ash is used to neutralize the acid puddle created at the bottom of the pool. The resulting sludge often requires a submersible pump and container, both of which have to be handled and cleaned carefully and the area rinsed.

When a pool is old and badly stained, the only option may be to replaster. Your pool tech will tell you if replastering is your best option.



During the pool refill process, we add a new batch of chemicals which will turn the tap water into pool water. Cooler weather works in favor of the acid wash, as fewer chemicals are needed to balance the pool.

If you need pool maintenance for your Phoenix, Arizona pool or spa, call us here at Serenity Pools. Our services include new installation set-up, professional maintenance of pools and spas, water features, and fountains. Call today! 480-370-0579.