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Calcium Hardness: How To Fix And Maintain It

Calcium Hardness: How To Fix And Maintain It
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Having a pool is a dream for most prospective homeowners, but it takes a lot of hard work to maintain one. One of the many things pool owners and pool professionals will have to deal with is calcium hardness.

Increasing calcium hardness in a pool is a challenge for many if the calcium level in the water seems to be too low. On the flip side, how to lower calcium hardness is another challenge if the calcium level is too high.

This article addresses calcium hardness, what it means, and how to deal with it. So make sure you till the very end.

What Is Calcium Hardness?

Calcium hardness refers to the calcium level present in your pool. Having too much calcium hardness in your pool is never a good thing; neither is having too little calcium. If you want your pool water to look and feel right, you have to do all that you can to make it balanced.

One common term you will encounter is “hard” or “hardness” as you read this article. It refers to the amount of minerals in your water.

Mineral content refers to:

  • Magnesium carbonates
  • Bicarbonates
  • Sulfates
  • Chloride

All these minerals combine to form total calcium hardness in the swimming pool. But, unfortunately, they also come together to cause cloudy water.

What Is the Cause of Calcium in Pools?

Different factors contribute to pool calcium hardness. You will be better able to regulate the total hardness ratio if you know what these factors are. Calcium hardness can occur if the water in your pool is exposed to snow or rain for a prolonged time.

Calcium levels may spike beyond acceptable levels as a result.

Another factor could be your water source. It may be that the calcium hardness was already present in the water long before you filed your pool. Whatever the factors, having too much or too little pool total hardness requires your urgent attention.

What Should My Pool’s Calcium Hardness Level Be?

Most people accept a standard level of pool hardness. Current industry standards range between 200-400 ppm in conventional swimming pools to ensure the proper chemical balance. It is generally accepted that a pH level of 100-250 is appropriate for spa pools and hot tubs. However, these volumes may differ depending on the user and what the pool is used for.

Water Too Soft- How to Increase Calcium Hardness in Pool

When pool water is considered too soft, it means that the pool water has low calcium hardness. That is, it is below the 200-400 ppm or 100-250 ppm-level. In such a situation, you will need to look for how to increase hardness in pool water. One of the most effective ways to do deal with low calcium hardness is to use, what we call, a pool hardness increase.

Digital Water Test Kit for Pools and Hot Tubs
  • Features a photometer which gives you a digital reading of test results.
  • Water resistant housing and carrying case provided.
  • Tests Free Chlorine, Total Chlorine, Bromine, PH, Alkalinity, Calcium Hardness, and Cyanuric Acid.
  • Uses liquid reagents for all test factors except Cyanuric Acid, which uses tablets.

How to Raise Calcium Hardness in Your Swimming Pool?

If your pool hardness is too low and has dropped below 150-100 ppm, a poop hardness increaser is an effective material. A perfect example of a hardness increaser is calcium chloride. Adding calcium to the pool or hot tub will raise the hardness level.

High Calcium Hardness 

Just as a pool can suffer from low calcium hardness, it can also suffer from high calcium hardness. If the pH level is too high, it will become over-saturated with particles and extraneous elements that are undesirable. Over time, you will begin to notice pool cloudiness.

In a scenario where the pool hardness is extremely high, you may not even be able to see the bottom of the pool as clearly as you should. The reason for this is that too much calcium causes the equipment to scale. Another way to know that pH levels are too high is if you begin to notice equipment clogging or blocked water flow.

Failure to address calcium pool hardness on time may damage your equipment.

How to Lower Calcium Hardness in Your Swimming Pool?

 So what do you do if you notice that the pH level in your pool is too high? You will have to take several steps to reduce the calcium hardness and prevent calcium buildup. One of the steps to take is to drain your pool of the existing hard water and refill it with fresh water.

Keeping Levels Perfect

Ensure that you keep the pH level in your swimming pool perfect at all times by draining the water at regular intervals.

Fix Problems as They Arise

Another way to prevent buildup is to make sure you fix problems as quickly as possible. Always clean your pool after any repair or enhancement.

Regularly Test Water

It may be that the calcium pool hardness is not caused by the swimming pool or the weather but by your water source. Because of this, it is a good idea to test calcium hardness as well as pH and total alkalinity often. If the pool hardness is high, then lower hardness in the pool. If it is too low, then raise it. Testing calcium hardness is a smart way to maintain a stable pH level. Also, be mindful of the pool chemicals you use in cleaning your swimming pool. Regular testing will ensure that your pool is properly balanced.

Keep Clean

Keeping your pool clean at all times is essential to protect your health and also to prevent calcium hardness. Certain organisms and mineral buildup can lead to pool hardness. Whether you use the pool regularly or not, make sure you clean it as often as possible. If your pool is an above-ground swimming pool, get a cover for it. It will improve the pool’s chemistry.

Balance Water

Also, make sure that the pool pH level is balanced. A calcium hardness increaser will fix the problem and balance calcium levels if the level is too low. However, water balance circulation and water balance calculation are critical.

Pool Mate Calcium Increaser for Swimming Pools, 25 Pounds
  • Calcium chloride for pools
  • Rapidly increases total hardness
  • Helps prevent corrosion or etching of pools

Calcium Hardness FAQs

What Increases Calcium Hardness?

Two factors are responsible for a rise in calcium hardness. They are water temperature and chemical imbalance caused by an increase in calcium. If the water temperature rises, calcium will begin to build because it is soluble in cold water. As for chemical imbalance, this occurs if the water contains a high dose of calcium or too little alkaline. Imbalance leads to calcium deposits and algae buildup. Another consequence is cloudy water.

What Happens if Calcium Hardness Is Too High?

If the calcium chloride is too high in your pool, it will become a breeding ground for algae. Your pool will also begin to develop color. Excess calcium or a high dose of dissolved calcium is bad for your pool.

Does Baking Soda Raise Calcium Hardness?

Yes, baking soda can raise calcium hardness. Baking soda contains calcium carbonate, and if you add it to your pool, the pH level will increase. For best results, add the chloride a few hours before or after treating the pool with soda ash or baking soda.

What Is Calcium Hardness Increaser Made Of?

A calcium increaser or a pool hardness increaser contains chloride, which is 97% granular chloride, to raise calcium hardness level. For example, when you add about 6 pounds of calcium chloride to 10,000 gallons of water, the pH level will rise by 50 ppm. Therefore, you can use an increaser to increase the calcium hardness level. Some other types of increasers also contain calcium carbonate.

Reduce or Raise Calcium Hardness Effectively

Calcium hardness is never a good or bad thing. It simply refers to the pH level in your pool.

In the presence of excess calcium in your pool, it will become cloudy and be exposed to algae growth, resulting in a horrible sight to behold. Also, if the pH level is below 150 ppm, that is not good enough. So to keep pH at a minimum level, make sure you change your pool water regularly and keep the pool clean at all times. If the pH level is too low, add baking soda or a dose of formulated calcium to it to raise the level to acceptable standards.

Pricing on this page was last updated on 2024-04-29