Understanding the Difference Between Corrosion and Scale

When it comes to water systems, corrosion and scale are two major problems that can compromise the safety, efficiency, and reliability of water systems.

Understanding the key differences between these two issues is essential for effective water treatment and equipment longevity as both issues require distinct approaches for prevention and treatment.


Corrosion is a gradual, destructive process that occurs when metals in your water systems, such as pipes and fixtures, react with certain environments. Corrosion causes the metal to degrade which can lead to reduction in strength and leaking. As metals corrode, they can release harmful substances such as lead or heavy metals into the systems, causing the water to become contaminated. Corroded pipes restrict the flow of water and results in reduced efficiency of water heating and distribution systems. Corrosion in water systems is inconvenient and costly and can lead to unplanned downtime for businesses to repair damages.


Scale is the accumulation of mineral deposits, primarily calcium and magnesium, on the interior surfaces of pipes and equipment. These minerals precipitate out of the water when it is heated, leading to the formation of scale, which restricts water flow. This restriction leads to a reduction in the overall efficiency of these systems, resulting in increased energy consumption. Consequently, the extra energy needed to heat water can lead to higher utility bills, imposing a significant financial burden to businesses. Furthermore, scale deposits can shorten the lifespan of water heaters and other appliances, necessitating more frequent replacements and incurring additional maintenance costs.

The Key Differences

Appearance: Corrosion often manifests as reddish or orange flakes in your water, indicating the presence of rust particles. Whereas scale typically presents as white or chalky deposits on faucets, showerheads, and the insides of pipes and appliances.

Causes: Corrosion is commonly caused by factors such as low pH levels, high oxygen content, and the presence of aggressive chemicals in the water. In contrast, scale results in high levels of dissolved minerals in the water, particularly in hard water areas.

Effects: Corrosion can weaken the structural integrity of plumbing, leading to leaks and reduced water quality, and costly repairs. On the other hand, scale buildup can reduce water flow and energy efficiency. It can also clog pipes and reduce the lifespan on appliances.

Prevention: Corrosion prevention often involves adjusting the pH level, installing corrosion-resistant materials or adding protective coatings to metal surfaces. To prevent scale, water softeners and descaling agents can be mitigated through the water systems.


In conclusion, both corrosion and scale are common issues in water treatment. Understanding the differences between them is crucial for maintaining a healthy and efficient water system. By staying informed and taking proactive measures, you can ensure that your water remains safe and reliable.