Acid washing a pool is a process used to clean and restore the interior surface of a pool, typically to remove stains, algae buildup, or calcium deposits that can’t be eliminated through regular cleaning. Though it’s an effective solution for heavily soiled pools, acid washing should only be done when absolutely necessary, as it involves using strong chemicals that can erode the pool's surface over time. This guide explains how to acid wash a pool safely and effectively.

Acid washing is ideal for pools with:

• Persistent stains from algae, minerals, or debris.
• Calcium buildup or scaling on the pool surface.
• A neglected pool with significant discoloration.

If your pool doesn’t have severe staining, consider other cleaning methods, as acid washing strips a thin layer of the pool’s surface, which can reduce its lifespan.

• Muriatic acid
• Protective gear (goggles, gloves, long-sleeve clothing, and a respirator)
• A sump pump
• A stiff pool brush
• Garden hose with a spray nozzle
• Baking soda (to neutralize acid)
• Plastic buckets
• A helper (optional but recommended)

1. Drain the Pool: Use a sump pump to remove all the water from the pool. Ensure you follow local regulations for draining pool water, as it may contain chemicals harmful to the environment.

2. Inspect the Surface: Once the pool is empty, inspect the surface for cracks, damages, or weak spots that might worsen with acid washing.

3. Protect Yourself and Surroundings: Wear proper protective gear and cover nearby vegetation or surfaces that could be harmed by acid splashes.

• In a plastic bucket, mix one part muriatic acid with four parts water. Always add acid to water, not the other way around, to prevent dangerous reactions.

• Starting at the deep end, pour the acid solution onto the pool surface in sections.
• Use the stiff brush to scrub the acid over the stained areas. The acid will fizz as it removes stains and buildup.
• Work quickly, as the acid should not sit on the surface for too long.

• Rinse each section thoroughly with water as you go. Use a garden hose to ensure no acid remains on the surface, as prolonged exposure can damage the pool.

• After completing the process, sprinkle baking soda over the rinsed surface to neutralize any remaining acid. Wash the pool thoroughly with water again.

• Once the pool is cleaned, ensure all acid residue is rinsed away.
• Refill the pool with water and balance the pool’s chemistry (pH, alkalinity, chlorine levels) before use.

• Always work in a well-ventilated area to avoid inhaling fumes.
• Keep children and pets away from the worksite.
• Never mix muriatic acid with other chemicals.

Acid washing is an effective but intensive pool maintenance process. While it can restore a stained robot pool to its original condition, it should only be performed when absolutely necessary. By following this guide and taking proper precautions, you can safely and effectively acid wash your pool and extend its aesthetic appeal.