Elevate Your Pool's Calcium: Simple Steps to Boost Water Hardness
Keeping a pool clean and healthy doesn’t just involve keeping the water clear or constantly checking the levels of chlorine. An essential factor that a lot of swimming pool owners neglect is calcium hardness balance in water. The calcium hardness signifies how much dissolved calcium is present in the pool water; it also is an essential component for prolonging the life of the pool surface, plumbing, and the quality of your water. Problems can arise if your pool water is too soft (lacking enough calcium) or too hard (with excess calcium). In this article we’ll take a look at the importance of calcium levels, how you can raise them, and the difference it can make to the health of your pool.
Table of content
- 1. What is calcium hardness?
- 2. The Trouble with Low Calcium Hardness
- 3. The High Calcium Hardness Problem
- 4. How to Raise the Calcium Hardness of Your Pool
- 5. Regular Monitoring of Calcium Levels
- 6. Maintaining Balanced Calcium Levels for a Healthy Future
- 7. Conclusion: The Importance of Boosting Calcium Levels
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What is calcium hardness?
Before we get into how to raise calcium hardness, it’s important to know what it actually means. Calcium hardness refers to the dissolved calcium and magnesium in the water. Typically, it is described in parts per million (ppm). The calcium hardness range for most pools is from 200 to 400 ppm. If it’s too low, the water can become corrosive, meaning it will begin leaching calcium from the pool surfaces, the plumbing, and the equipment. This causes the pool surface to deteriorate and develop rough spots, and in some cases, even cracks in the plaster.
Too much calcium in the water, on the other hand, makes hard water. This may result in an accumulation of scale on pool surfaces and plumbing. Calcium can accumulate on your tiles, in your pipes, and on your pool’s heater, causing your equipment to work harder. That’s why balanced calcium is an important part of pool maintenance.
The Trouble with Low Calcium Hardness
Aggressive water is caused by low calcium hardness. In other words, it will begin to leach calcium from surfaces, including your pool’s plaster, which compromises the structure over time. This can cause damage you can see, like cracks, pitting, and a rough pool surface. Low calcium can also contribute to cloudy water. Water causes a lot of particles in the water; the particles make the water look dirty as the water looks for calcium to "feed" on.
Low calcium levels can also strain your pool's filtration system. As the plaster starts to deteriorate, tiny bits break off, eventually releasing into the water and clogging your pool’s filter. This can restrict water movement and make for ineffective cleaning, allowing bacteria and algae to run rampant in your pool.
The High Calcium Hardness Problem
If low calcium is detrimental to the pool, high calcium is just as problematic. But too much scaling occurs, a calcium buildup known as "hard" water. Scale is a difficult, chalky deposit that develops on the pool’s surface, plumbing, and also other devices. Not only does this make for a very undesirable pool appearance, but it can also cause damage to your pool’s filtration system, potentially reducing the life of your pool heater.
Excessive calcium can lead to problems with your pool’s chemistry. If the water has excessive calcium, it can make it difficult to synergize other significant factors, including pH and alkalinity. That results in instability in the water, which will create more maintenance issues.
How to Raise the Calcium Hardness of Your Pool
If you’ve tested and discovered that your pool calcium hardness is too low, then you need to take action to increase the levels. If you need to increase calcium hardness, it's been quite simple to do by adding calcium chloride to your pool. One of the most common compounds used for raising calcium levels in swimming pools is calcium chloride, which is available in both granular and liquid forms.
Follow these steps for how to add calcium to your pool:
1. Determine Your Calcium Hardness:
Before you start, test your pool water to find your current calcium hardness. Test for calcium levels using a pool test kit. If it is on the low side (below 200 ppm), you will have to bring it up.
2. Calculating the Required Amount:
After determining your calcium hardness level, you can calculate the amount of calcium chloride you need to add. Calcium chloride packaging will usually tell you how much to add depending on your pool’s volume and the difference between your pool’s current and desired calcium level.
3. Add the Calcium:
With the churning action of the water, slowly add the calcium chloride into the pool, near the deep end if possible. This will enable the calcium to disperse and circulate throughout the pool uniformly.
4. Run Your Pool Pump:
Following the inclusion of the calcium chloride, let your pool pump circulate for several hours. This helps the calcium dissolve and spread throughout the water. It’s crucial to ensure that the pool pump is running so that the calcium doesn’t settle in one spot.
5. Retest After A Few Days:
Test the calcium hardness of your pool one more time after another day or two has passed to make sure that the levels have reached the proper range (200-400 ppm). If they remain low, you may have to add calcium chloride to the solution.
Regular Monitoring of Calcium Levels
Be sure to test calcium hardness in your pool regularly to ensure balance. While you should check your pool water at least once a month, harsher pool usage or even significant weather changes (think heavy rain or extreme heat) may require you to check more often. Regular testing keeps you ahead of any disturbances, such as calcium depletion or overconcentration.
If your calcium levels are consistently elevated, you'll likely need to partially drain your pool and refill it with fresh water to dilute the calcium concentration. drain the water gently, and at no time should you have a drain of more than 1–2" of water. Structural problems with your pool will occur at this point. If in doubt, always consult a pool professional.
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Maintaining Balanced Calcium Levels for a Healthy Future
Keeping calcium levels balanced is an essential part of keeping your pool in good working order for years to come. Maintaining appropriate calcium levels will help protect the plaster and scale and keep your filtration system operating properly. It also helps to balance other chemicals in the water, such as pH and alkalinity, leaving your pool water always safe and pleasant to swim in.
A pool with proper calcium levels is also easier to manage. So you won’t have to spend as much time cleaning scale deposits or getting rid of cloudy, dirty water. This is not only time-saving but also cost-saving since you will not have to replace pool equipment so often.
Conclusion: The Importance of Boosting Calcium Levels
So ultimately, raising your levels of calcium is crucial. Raising calcium levels in your pool might seem like a minor detail, but it plays a significant role in the health of your pool. Keeping the water hardness to an optimal regime protects the surfaces, plumbing, and equipment of your pool from being damaged. By regularly testing and keeping your calcium levels in a proper range, you will make your pool easier to maintain and its waters clear and inviting for years to come.
Whether you're a new pool owner or have had a pool for years, understanding the role of calcium in water chemistry and how to adjust it is an essential skill. With just a little bit of effort, you can ensure your pool is safe, beautiful, and ready for fun all season long.