what is pool scale-and how do you get rid of it?

What Is Pool Scale—and How Do You Get Rid of It?

Have you ever noticed a white chalky film on your pool tile, walls, ladders, or around your waterline? That’s most likely pool scale. In South Florida, where heat and evaporation are constant, scale is a common (but frustrating) issue for many pool owners. In this blog, we’ll break down what causes pool scale, the difference between types of scale, and how to safely get rid of it—and keep it from coming back.

What Is Pool Scale?

Pool scale is a buildup of minerals, primarily calcium, that forms hardened deposits on pool surfaces. It occurs when the water is chemically unbalanced—specifically, when the calcium hardness and pH are too high. As water evaporates in the Florida heat, it leaves behind these mineral deposits that bond to surfaces.

Types of Pool Scale

1. Calcium Carbonate: This is the most common type and looks like white, flaky deposits. It’s relatively easy to remove with scale remover or a pumice stone.

2. Calcium Silicate: This is a tougher, greyish-white scale that forms over time. It takes longer to develop and is much harder to clean—often requiring professional acid washing or mechanical scraping.

What Causes Pool Scale?

• High calcium hardness levels
• High pH and total alkalinity
• Heat and rapid evaporation (very common in South Florida)
• Use of hard water when refilling the pool
• Poor water circulation or dead zones in the pool

How to Get Rid of Pool Scale

1. Identify the Type of Scale: Drop a few drops of muriatic acid on the scale. If it fizzes, it’s calcium carbonate. If it doesn’t, it’s likely calcium silicate, which is harder to treat.

2. Use a Scale Remover: For mild calcium carbonate buildup, commercial scale removers or vinegar can be used with a scrub brush or pumice stone. Always follow the manufacturer’s directions.

3. Acid Wash for Severe Scale: If scale is covering large areas or is silicate-based, professional acid washing may be needed. This involves draining the pool and using a diluted acid solution to break down the mineral deposits.

4. Balance Your Water: After cleaning, test and adjust your pool chemistry. Ideal ranges:

• Calcium Hardness: 200–400 ppm
• pH: 7.2–7.6
• Total Alkalinity: 80–120 ppm

How to Prevent Scale in the Future

• Test and balance water weekly—especially during the summer and dry season
• Use a sequestering agent to prevent calcium buildup
• Brush pool walls and tiles weekly to prevent deposits
• Improve circulation and ensure return jets are angled properly

Bonus Tip: If you use well water or hard municipal water to fill your pool, consider using a pre-filter to reduce minerals before they even reach your pool!

When in Doubt, Call the Pros

If you’re not sure what type of scale you’re dealing with—or your pool has major staining or deposits—call the team at Sparkling Pools. We’ll diagnose the problem and recommend the best cleaning and prevention plan for your pool and finish.

□ Call us at 305‑823‑5438 or visit our store in Miami Lakes for help with scale and all your pool care needs.