What Does Calcium Hardness Increaser Do?

Often sold in powder form, calcium hardness increasers contain the chemical compound of calcium chloride dihydrate. They're used to raise the Total Hardness level in a pool, which can help restore balanced water chemistry. Properly managing the calcium hardness of your pool is crucial for preventing issues such as the formation of calcium deposits, which can coat pool surfaces and equipment. When your pool's calcium hardness is too low, it can lead to the corrosion of metal equipment and damage to concrete and plaster. Therefore, maintaining the appropriate level of calcium is essential to avoid these problems.

To achieve the ideal balance, it's important to understand how much calcium your pool needs to reach the recommended range. The level of calcium hardness, often measured in parts per million (ppm), contributes to the overall Total Hardness of your pool water. The Total Hardness combines both calcium and magnesium salts in the water, ensuring that your pool remains in optimal condition. High calcium hardness can lead to various issues, so it's essential to manage it effectively.

In addition to preventing scale formation, maintaining proper pool calcium hardness with a calcium hardness increaser also safeguards your equipment from corrosion and extends their lifespan. This granular product is easy to apply and dissolves quickly, making it a convenient choice for pool owners of all sizes. Furthermore, it prevents stains and etching on pool surfaces, contributing to the overall aesthetic appeal of your pool.

Recommended Calcium Hardness Levels

Ideally, you want your calcium hardness to be between 200 and 400 ppm. It's important to actively manage calcium hardness, testing calcium hardness regularly, along with pH and total alkalinity in order to keep your water balanced and protect your equipment and surfaces. If you have excess calcium in your pool, it can lead to various issues, so maintaining the recommended range is essential for optimal pool water quality.

Addressing the Formation of Scale

One of the biggest problems is that calcium is soluble at a lower temperature than other chemicals, so it tends to form deposits when your water gets cold. These deposits, called scale, can corrode surfaces, particularly concrete pool surfaces, and make it difficult for heaters to function properly because they block the passage of heat. They can also clog filters and snag bathing suits. To address these issues, it's important to raise calcium hardness to an appropriate level and maintain it within the recommended range. The specific amount of calcium you need to add will depend on your pool's size and current water conditions.

Protects Your Roof

In addition to being a key water balance factor, calcium hardness can help prevent corrosion of pool equipment and surfaces, potentially saving you from expensive repairs. This is because calcium acts as a buffer against other chemicals such as chlorine and alkalinity, helping to maintain their levels. However, if the levels are too low, the corrosive effects of these other chemicals can damage the surface of your pool, leading to the need for costly repairs.

Testing Calcium Hardness

Ideally, your calcium level should be between 200 and 400 ppm. It is important to test your water on a regular basis to ensure it stays within the range. It also helps to test it on a weekly basis after any significant changes such as rain, adding a new chemical, or heavy swimmer use.

You can use a liquid test kit to measure your calcium hardness, although you should always read the instructions carefully. Generally, the process involves filling a clean test vial with pool water and then comparing it to a reference chart or table.

Prevents Corrosion

Like pH and alkalinity levels, calcium hardness needs to be in a certain range. If it isn’t, it can lead to damage to your pool and equipment. Having calcium hardness too low can cause metal equipment, like heaters, pumps and filters to corrode. This can cost you a lot of money in repairs and replacements. Properly balanced calcium hardness prevents the water from attacking your equipment and prolongs their lifespan.

Prevents Damage to Equipment

This product is a must for all pool owners to prevent damage to equipment caused by low calcium levels. When calcium hardness is too low, water becomes aggressive and attacks all metal equipment including liner, heaters, pumps, and filters. This can cause expensive equipment repairs or even replacements. Keeping calcium levels in the optimal range protects equipment, prolonging its lifespan and saving you money.

Proper Dissolution and Application

This granular product is easy to apply and dissolves quickly, making it the perfect choice for a variety of swimming pool sizes. The convenient size allows you to use this product in smaller increments as needed, reducing the amount of time spent on pool maintenance. It also provides an excellent source of calcium to your pool, preventing surface staining, etching, and scaling. This product is available in two bags of 20lbs, providing you with an ample supply to keep your pool and spa water properly balanced.

Prevents Stains

Keeping the calcium levels in your pool and spa within the recommended range prevents surface stains, equipment corrosion, and other damage to the water. It also improves chemical stability, which helps protect against the corrosive effects of chlorination. low calcium hardness

If your pool's calcium hardness level is too low, a small addition of calcium hardness increaser brings it up to the optimal range. This helps prevent foaming, equipment damage, and water cloudiness. Using a high-quality calcium hardness increaser ensures that the levels are safe and effective.

Using a Quality Calcium Hardness Increaser

A good calcium hardness increaser should contain a high concentration of calcium chloride and be easy to dissolve in your pool water. It should also be clear in color so you can easily identify the proper amount to add. You should always follow the instructions on the product packaging and consult a professional if you have any questions or concerns about the proper use of this pool chemical.

Best Practices

If you have trouble maintaining your pool's calcium hardness levels, you may need to use a different type of chemical, such as calcium hypochlorite. However, this is not a great option because it also raises chlorine levels. This can make the water too hard to swim in and cause itchy eyes and skin. Plus, it can also cause a buildup of magnesium deposits on pool surfaces. The best way to avoid this is to purchase a quality calcium hardness increaser that is specifically formulated for pool water. You can find one of these products at a reliable online pool store.

Maintaining Water Chemistry

Properly managing the calcium hardness of your pool is an essential aspect of maintaining water chemistry. It goes hand in hand with other key parameters such as pH and alkalinity. When all these factors are within their recommended ranges, you can enjoy a crystal-clear pool with water that's gentle on swimmers' skin and eyes. Neglecting calcium hardness can lead to a cascade of issues that affect the overall pool experience. So, it's not just about equipment and surfaces; it's about the comfort and well-being of those using your pool.

Balance and Longevity

By using a calcium hardness increaser to maintain the right levels, you're not only safeguarding your equipment but also ensuring the longevity of your pool's surfaces. An investment in a quality calcium hardness increaser can lead to cost savings in the long run by preventing damage that might necessitate expensive repairs. This preventive approach is particularly important for those living in regions with fluctuating water hardness levels, as constant adjustments are often needed to keep your pool water in its ideal state.

Eco-Friendly Option

Many calcium hardness increasers are formulated to be environmentally friendly, which is another reason to choose them over alternative methods. These products are designed to minimize any negative ecological impact while effectively achieving their purpose. By selecting eco-friendly options, you can contribute to the well-being of your local ecosystem and reduce the overall environmental footprint of your pool maintenance routine.


In conclusion, a calcium hardness increaser is an essential tool for any pool owner committed to maintaining water quality, protecting equipment, and enhancing the overall pool experience. By understanding its function and the recommended calcium hardness levels, you can ensure that your pool remains a source of relaxation and enjoyment. Regular testing, proper dissolution, and the use of high-quality products will help you avoid the pitfalls of low calcium hardness, from equipment damage to water quality problems. Embracing these best practices and eco-friendly solutions is not only beneficial for your pool but also for the environment, ensuring that you can make the most of your pool season after season.

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