A Guide To Calcium Hardness In Swimming Pools
Swimming pool maintenance takes time, thought, money, and effort, as there are various maintenance aspects for pool owners to consider. One of the most important aspects of pool maintenance is calcium hardness. If you're a new pool owner or are planning to invest in a swimming pool, read on, as this article will tell you all you need to know about calcium hardness and its importance. So, without delaying things any further, let's understand what calcium hardness is and the role it plays in keeping your pool safe for swimming.
Calcium hardness: What is it?
Calcium hardness, quite simply, is a measurement that’s helpful in understanding the level of calcium in the water of your swimming pool. If you didn’t know it already, let us tell you that calcium has a vital role to play in maintaining the chemistry of your pool water. However, while calcium is important, too much of it can increase water hardness, which can adversely impact not just the safety of the pool water but also the safety of various pool equipment.
Ideal calcium hardness levels
Calcium hardness is measured in parts per million or ppm, and the ideal level should be somewhere around 150 – 400 ppm. So, quite simply, if the calcium hardness level of your pool water is below 150 ppm or higher than 400 ppm, you need to adjust calcium levels. We’ll get to how you can lower or raise the calcium level in the pool water later. First, though, it’s important to understand how high or low calcium hardness can impact your swimming pool.
High calcium hardness
When the calcium levels in your pool water are excessively high, i.e. above 400 ppm, the water will start to look somewhat cloudy and murky. The reason for this is water saturation, which results in calcium precipitating out. While short-term calcium precipitation isn’t a cause for concern, over a long time, it can lead to scaling. It’s a process that involves the calcium coating and clinging to all the things it comes into contact with inside the pool water.
For instance, the masonry and tiles submerged in water will start to have a scaly, white appearance due to calcium deposits. Also, your pool equipment and plumbing will be in danger. As calcium deposits build up on your pool machinery and plumbing, they’ll have to put in more work to do the jobs they’re supposed to. This will lead to them becoming more and more inefficient over time. For instance, if your pool pump has to work harder to circulate water around the pool, it will lead to higher utility bills.
Apart from the potential of higher utility bills, you also need to worry about the lifespan of your pool equipment. If the calcium levels go unchecked, they can drastically decrease the lifespan of the machinery. It’s important to remember that even the most affordable pool machinery comes at a steep cost. In the worst-case scenario, you may have to replace some of your equipment due to the damage caused by high calcium hardness.
Low calcium hardness
Low calcium hardness is a state of extremely low calcium levels in pool water, i.e. below 150 ppm. If your pool water appears excessively sparkling or clear, it’s a sign of low calcium hardness. It can be hard to diagnose low calcium hardness with the naked eye as, typically, most people tend to think of sparkling and clear water as safe water.
When calcium levels are low, the water will gradually become corrosive. In this situation, when the water comes into contact with your pool’s plaster, concrete, or tiles, it will suck out the calcium from them. In the long run, this can devastate your pool’s masonry due to etching, which will result in scars and blemishes. Repairing this can be incredibly draining on your finances.
Low levels of calcium are also associated with drastically reduced pool alkalinity. Metal items will experience corrosion, and this can lead to severe damage being sustained by your pool’s mechanical parts and railing.
How to lower your pool's calcium hardness level
You can employ one or more methods to reduce the calcium hardness level of your pool water, which include:
- Addition of muriatic acid: Adjusting alkalinity can reduce calcium hardness levels, and muriatic acid is among the best alkalinity adjusters. Most pool centres and home improvement stores sell muriatic acid, but if you can’t find any near you, you’re sure to get it online. 2 – 3 capfuls of it should be enough, but you’ll have to give it around 12 hours to work its magic.
- Drain and replace your pool water: Draining and replacing pool water is an effective way of reducing calcium hardness. It’ll get rid of the calcium-rich water and replace it with fresh water. However, you’ll have to put in some work to ensure proper pool water chemistry. Also, this won’t work if your local water supply has high calcium levels.
- Use a flocculant: Flocculant use can result in the calcium in the pool water solidifying, following which it will be precipitated out. You can clean the solidified calcium by hand.
How to raise your pool's calcium hardness level
For raising the calcium hardness level of your pool water, you can add calcium chloride to it. However, you have to be cautious while adding calcium chloride. Adding too much of it can raise calcium levels significantly, which you wouldn’t want. The rule is to add 1 and 1/4 pounds of calcium chloride per 10,000 gallons for raising the calcium hardness level by 10 ppm. You can do the math and find out how much calcium you need to add to your pool water based on this rule.
Conclusion
Most new pool owners don’t pay attention to calcium hardness and other pool maintenance aspects as they’re busy treating themselves and their families to some relaxation in the water. While you should of course enjoy your swimming pool, you should always spare some thought at the back of your head for maintaining calcium hardness levels. Trust us – it’ll save you a lot of trouble and money in the long run.
When adding calcium chloride to your pool, the amount you need mostly depends on your pool’s current calcium hardness levels and how much you want to increase it. Generally, to raise the calcium hardness by 10 ppm in a standard 40,000-litre pool, you’ll want to add about 0.7 kilograms of calcium chloride. It’s a good idea to test your pool water regularly and make adjustments, since keeping the calcium hardness between 200-400 ppm helps avoid corrosion and scale build-up. Remember to dissolve the calcium chloride in a bucket of water before putting it into the pool, and spread it out evenly for the best results.
Low calcium hardness in swimming pools can happen for a few reasons. A big one is when you regularly add fresh water, which can dilute the calcium concentration. Also, using water softeners can lower calcium levels because they often swap out hardness ions for sodium. Other factors include evaporation, which might leave calcium behind while concentrating other chemicals, and frequently using acidic cleaners that can strip calcium from the pool surfaces. Lastly, skipping regular water chemistry checks can make the problem worse, leading to low calcium hardness in the pool.
If you find that your pool’s calcium hardness is too high, there are a few effective methods to lower it. One common approach is to partially drain the pool and refill it with fresh water, as this water generally contains lower calcium levels. Be sure to consider local water quality when refilling, as this can vary. Additionally, you can use a calcium binding agent, which works by binding calcium and preventing it from forming scale on your pool’s surfaces and equipment. However, it’s important to note that this method serves as a temporary solution and may require repeated applications over time.
High calcium hardness can lead to several issues that can compromise your pool’s overall health. One of the most noticeable effects is the potential for scale formation on pool surfaces and equipment, which can not only detract from the aesthetic appeal of your pool but also lead to costly repairs. Furthermore, high calcium levels can create cloudy water, making it less inviting for swimmers, while also reducing the effectiveness of sanitisers used to keep the water clean and safe. Swimmers may experience discomfort due to the hardness of the water, which can irritate skin and eyes, making regular monitoring of calcium levels essential for a pleasant swimming experience.
After adding calcium to your pool, it is generally recommended to wait at least 24 hours before swimming. This waiting period allows the calcium to dissolve properly and distribute evenly throughout the water, ensuring that the chemical balance is right for swimming. It’s always a good practice to check the water chemistry before jumping in, as this will give you peace of mind regarding the safety and comfort of the water. Regular monitoring and maintenance will help keep your pool in optimal condition for enjoyment.
A Guide To Calcium Hardness In Swimming Pools
Swimming pool maintenance takes time, thought, money, and effort, as there are various maintenance aspects for pool owners to consider. One of the most important aspects of pool maintenance is calcium hardness. If you're a new pool owner or are planning to invest in a swimming pool, read on, as this article will tell you all you need to know about calcium hardness and its importance. So, without delaying things any further, let's understand what calcium hardness is and the role it plays in keeping your pool safe for swimming.
Calcium hardness: What is it?
Calcium hardness, quite simply, is a measurement that’s helpful in understanding the level of calcium in the water of your swimming pool. If you didn’t know it already, let us tell you that calcium has a vital role to play in maintaining the chemistry of your pool water. However, while calcium is important, too much of it can increase water hardness, which can adversely impact not just the safety of the pool water but also the safety of various pool equipment.
Ideal calcium hardness levels
Calcium hardness is measured in parts per million or ppm, and the ideal level should be somewhere around 150 – 400 ppm. So, quite simply, if the calcium hardness level of your pool water is below 150 ppm or higher than 400 ppm, you need to adjust calcium levels. We’ll get to how you can lower or raise the calcium level in the pool water later. First, though, it’s important to understand how high or low calcium hardness can impact your swimming pool.
High calcium hardness
When the calcium levels in your pool water are excessively high, i.e. above 400 ppm, the water will start to look somewhat cloudy and murky. The reason for this is water saturation, which results in calcium precipitating out. While short-term calcium precipitation isn’t a cause for concern, over a long time, it can lead to scaling. It’s a process that involves the calcium coating and clinging to all the things it comes into contact with inside the pool water.
For instance, the masonry and tiles submerged in water will start to have a scaly, white appearance due to calcium deposits. Also, your pool equipment and plumbing will be in danger. As calcium deposits build up on your pool machinery and plumbing, they’ll have to put in more work to do the jobs they’re supposed to. This will lead to them becoming more and more inefficient over time. For instance, if your pool pump has to work harder to circulate water around the pool, it will lead to higher utility bills.
Apart from the potential of higher utility bills, you also need to worry about the lifespan of your pool equipment. If the calcium levels go unchecked, they can drastically decrease the lifespan of the machinery. It’s important to remember that even the most affordable pool machinery comes at a steep cost. In the worst-case scenario, you may have to replace some of your equipment due to the damage caused by high calcium hardness.
Low calcium hardness
Low calcium hardness is a state of extremely low calcium levels in pool water, i.e. below 150 ppm. If your pool water appears excessively sparkling or clear, it’s a sign of low calcium hardness. It can be hard to diagnose low calcium hardness with the naked eye as, typically, most people tend to think of sparkling and clear water as safe water.
When calcium levels are low, the water will gradually become corrosive. In this situation, when the water comes into contact with your pool’s plaster, concrete, or tiles, it will suck out the calcium from them. In the long run, this can devastate your pool’s masonry due to etching, which will result in scars and blemishes. Repairing this can be incredibly draining on your finances.
Low levels of calcium are also associated with drastically reduced pool alkalinity. Metal items will experience corrosion, and this can lead to severe damage being sustained by your pool’s mechanical parts and railing.
How to lower your pool's calcium hardness level
You can employ one or more methods to reduce the calcium hardness level of your pool water, which include:
- Addition of muriatic acid: Adjusting alkalinity can reduce calcium hardness levels, and muriatic acid is among the best alkalinity adjusters. Most pool centres and home improvement stores sell muriatic acid, but if you can’t find any near you, you’re sure to get it online. 2 – 3 capfuls of it should be enough, but you’ll have to give it around 12 hours to work its magic.
- Drain and replace your pool water: Draining and replacing pool water is an effective way of reducing calcium hardness. It’ll get rid of the calcium-rich water and replace it with fresh water. However, you’ll have to put in some work to ensure proper pool water chemistry. Also, this won’t work if your local water supply has high calcium levels.
- Use a flocculant: Flocculant use can result in the calcium in the pool water solidifying, following which it will be precipitated out. You can clean the solidified calcium by hand.
How to raise your pool's calcium hardness level
For raising the calcium hardness level of your pool water, you can add calcium chloride to it. However, you have to be cautious while adding calcium chloride. Adding too much of it can raise calcium levels significantly, which you wouldn’t want. The rule is to add 1 and 1/4 pounds of calcium chloride per 10,000 gallons for raising the calcium hardness level by 10 ppm. You can do the math and find out how much calcium you need to add to your pool water based on this rule.
Conclusion
Most new pool owners don’t pay attention to calcium hardness and other pool maintenance aspects as they’re busy treating themselves and their families to some relaxation in the water. While you should of course enjoy your swimming pool, you should always spare some thought at the back of your head for maintaining calcium hardness levels. Trust us – it’ll save you a lot of trouble and money in the long run.
When adding calcium chloride to your pool, the amount you need mostly depends on your pool’s current calcium hardness levels and how much you want to increase it. Generally, to raise the calcium hardness by 10 ppm in a standard 40,000-litre pool, you’ll want to add about 0.7 kilograms of calcium chloride. It’s a good idea to test your pool water regularly and make adjustments, since keeping the calcium hardness between 200-400 ppm helps avoid corrosion and scale build-up. Remember to dissolve the calcium chloride in a bucket of water before putting it into the pool, and spread it out evenly for the best results.
Low calcium hardness in swimming pools can happen for a few reasons. A big one is when you regularly add fresh water, which can dilute the calcium concentration. Also, using water softeners can lower calcium levels because they often swap out hardness ions for sodium. Other factors include evaporation, which might leave calcium behind while concentrating other chemicals, and frequently using acidic cleaners that can strip calcium from the pool surfaces. Lastly, skipping regular water chemistry checks can make the problem worse, leading to low calcium hardness in the pool.
