Well, we all know how essential calcium is for our healthy bones and teeth, but this calcium can be dangerous when it exothermically reacts with acids & water. When the reacted calcium comes in contact with our body moisture, it causes severe skin irritation. If swallowed leads to a stomach infection and esophagus with fatal outcomes. 

Isn’t that scary? Not only this, calcium deposits in and around your pool would contribute to the corrosion of your pool’s metal fittings. It leaves ugly white stains that damage the overall curb appeal of your swimming pool. And, finally, it creates tiny pinhole leaks in various pool equipment. 

Calcium levels in a pool can be controlled through a process called “sequestering.” This involves adding a chemical called a sequestrant to the water, which binds with the calcium ions and makes them less likely to form scale on surfaces or equipment. It is important to test the calcium levels in your pool regularly and adjust the sequestrant as needed.

Additionally, maintaining proper pH and total alkalinity levels can also help prevent calcium buildup. It is also recommended to use a good quality pool algaecide to prevent the formation of calcium scale on pool surfaces. It’s always best to consult with a professional pool service to determine the best course of action for your specific pool and needs.

If you don’t invest time and effort in pool maintenance, you are going to come across visible spots of calcium on the flooring, tiles, and walling of your pool. But, don’t you worry, as here in this article, we’ll educate you about calcium in the pool, the reasons, how to identify it, and the best methods to deal with it. So, let’s scroll down and have a look:

Reasons for Calcium in the Pool

There are a few primary reasons for the accumulation of calcium in your swimming pool.

Hard Water

The hard water brings & leaves behind calcium. If your house is getting hard water, you can quickly identify stubborn white spots of calcium in the tubs, sinks, and faucets. 

You can even call a specialist to determine the amount of hardness in the water supplied to your area.


Some parts of the world have constant high temperatures throughout the year, such as the US Southern part. It means the chemicals such as chlorine added into the pool evaporate quickly. 

So, we will put more chemicals in the water to maintain its hygiene, but lead to higher calcium levels through chlorine. 

One way to prevent this is by investing in constructing a pool enclosure. It will prevent the direct rays of the sun from heating the pool and causing a chemical imbalance. 


Evaporation is the process by which water molecules turn from liquid to gas and escape into the atmosphere. In a swimming pool, evaporation can occur naturally due to the sun’s heat and wind. When water evaporates from a pool, the remaining water becomes more concentrated with dissolved minerals and chemicals, which can lead to an increase in calcium levels if the source water is high in calcium.

To minimize evaporation and its effects on calcium levels, pool owners can use a pool cover to reduce the surface area exposed to the sun and wind, which can help to slow down evaporation. Additionally, maintaining the proper chemical balance and pH levels in the pool can also help prevent calcium buildup.

It’s also important to check the water level regularly and top it off with fresh water to avoid high mineral concentrations in the pool.


Backwashing is the process of reversing the flow of water through a pool filter to remove accumulated dirt and debris from the filter bed. When a pool filter is backwashed, the water flows in the opposite direction, flushing out the accumulated dirt and debris and expelling it out of the filter system.

During backwashing, the water in the filter bed can be released into the pool and this can cause an increase in the calcium levels in the pool if the water in the filter bed is high in calcium.

To minimize the impact of backwashing on calcium levels, pool owners can use a filter media that is less likely to accumulate calcium, such as a D.E filter or a cartridge filter. Additionally, regular maintenance and cleaning of the filter can help to remove accumulated calcium before it gets released into the pool during backwashing.

It’s recommended to test the water after backwashing to ensure the calcium levels are still within the recommended range and adjust accordingly. Also, it’s best to follow the manufacturer’s instructions for backwashing and cleaning the filter to ensure proper function.


Leakage can be a cause of increased calcium levels in a swimming pool because it can allow water from outside sources, such as soil or groundwater, to enter the pool. This external water can be high in calcium and other minerals, which can then increase the overall calcium levels in the pool.

To detect and fix a leak in a swimming pool, there are a few things you can do:

  1. Check the pool’s water level: If the water level in the pool is consistently dropping, it may indicate a leak in the pool or its plumbing.

  2. Listen for unusual noises: Leaks in the pool or its plumbing can sometimes cause unusual noises, such as gurgling or bubbling sounds.

  3. Check for visible signs of leaks: Look for any visible signs of leaks, such as water seeping out of the pool, cracks or holes in the pool, or water around the pool equipment.

  4. Use a leak detection kit: There are special kits available that can help detect leaks in a pool or its plumbing.

  5. Call a professional: If you suspect a leak but can’t find it, it may be best to call a professional pool technician to help find and fix the leak.

If you have a leak in your pool, it is important to address it as soon as possible to prevent further damage and minimize the impact on calcium levels. A professional pool technician can help you identify and fix the leak, and also recommend a course of action to minimize the impact on the pool water chemistry.

Improper chemical balance

Maintaining the proper chemical balance and pH levels in a swimming pool is essential for preventing calcium buildup and other issues. When the pH and total alkalinity levels are not properly balanced, it can lead to calcium precipitation, which can cause scaling on pool surfaces and equipment.

The pH level of a pool should be between 7.2 and 7.8, and the total alkalinity should be between 80 and 120 parts per million (ppm). If the pH is too low, it can cause the water to become acidic, which can corrode pool equipment and surfaces. If the pH is too high, it can cause the water to become basic, which can cause calcium precipitation and scaling.

To prevent calcium buildup and maintain the proper chemical balance, pool owners should regularly test the pH and total alkalinity levels in their pool and adjust as needed. They should also regularly test the calcium levels and add a sequestrant or scale inhibitor as needed.

Inadequate cleaning

Inadequate cleaning of a swimming pool can lead to calcium buildup on pool surfaces, equipment, and fixtures. Calcium buildup can occur when calcium ions in the water attach to surfaces, forming a hard, white deposit known as scale. This can occur when the pool is not cleaned regularly, or when the pH and total alkalinity levels are not properly balanced.

To prevent calcium buildup and maintain a clean pool, pool owners should:

  1. Regularly brush and vacuum the pool: This helps remove dirt and debris from the pool surfaces and can also help prevent calcium buildup.

  2. Clean the pool filter: A dirty filter can lead to a buildup of calcium and other minerals, so it’s important to clean or replace the filter as needed.

  3. Use a calcium scale remover: If calcium buildup does occur, a calcium scale remover can be used to dissolve the scale and make it easier to remove.

  4. Maintain proper water chemistry: Keeping the pH and total alkalinity levels within the recommended range can help prevent calcium buildup.

  5. Drain and refill the pool: Draining and refilling the pool every few years can help to remove accumulated calcium and other minerals and to maintain a clean pool.

How Can You Distinguish Calcium?

Mainly, there are two types of calcium crystals. One is the Calcium silicate, and the other is the calcium carbonate. The former appears like a knotted rope on plaster and metal. 

Calcium carbonate is a crusty deposit at the corners of your swimming pool and appears like a flaky substance. 

Methods to Eliminate Calcium in the Pool

Now, how to get rid of calcium scaling? Here are three proven effective yet simple methods:-


Vinegar is commonly found in our kitchen. It is a natural cleaning agent. But it only helps in removing the early appearance of the calcium deposit. 

Have a brush and a spray bottle with vinegar to clean the areas wherever there are signs of calcium scaling. 

Spray on the affected areas and brush them. If the white signs don’t go, then you may try other methods below.

Muriatic Acid

It is a powerful cleaning product, should be used carefully, and avoid diving into the pool immediately treating the pool water with muriatic acid. It is vital to use Google, hand gloves, and other protective gear when using it. 

Pour the solution into your pool water slowly, and let it mix. After an hour or day, start rubbing the pool tiles using a non-abrasive scouring pad. 

Invest in a Pool Cover to Prevent Calcium Growth 

Finally, it is best to prevent the formation of calcium. And it involves investing in a high-quality pool cover. First, it will prevent the chemical balance in the water that causes calcium scaling, and second, prevent the direct sunlight from heating the pool equipment in operation, those heat releases calcium. 

If you think pool covers are a mess, you’ve to manually cover and uncover them, right? You are wrong, there have been recent advancements in terms of ease of use for pool covers these days, and one such innovation is the pool cover reel. It retracts and extends out of the pool automatically will a flick or switch or a push of a button — no elbow grease is needed.

So, to know more about calcium deposits in the pool, you must rope in an expert to advise you. 

Categories: General

Nicolas Desjardins

Hello everyone, I am the main writer for SIND Canada. I've been writing articles for more than 12 years and I like sharing my knowledge. I'm currently writing for many websites and newspapers. I always keep myself very informed to give you the best information. All my years as a computer scientist made me become an incredible researcher. You can contact me on our forum or by email at [email protected].