how to reduce calcium hardness in pool

How to Reduce Calcium Hardness in Pool

by | May 26, 2023

If you need help maintaining clear and balanced water in your swimming pool, call the experts at the nearest Classic Marcite today.

Knowing how to reduce calcium hardness in pools is important to keeping pool water clear and balanced. When the calcium level is too high, excess minerals in the water make it challenging to maintain proper pH and alkalinity levels. Achieving the optimal levels for a clean and clear swimming pool requires adding pool chemicals more frequently, and adding more of them.

To achieve the ideal water hardness, you may need to lower the calcium level. There are several ways you can do this. 

The Ideal Swimming Pool Water Hardness 

If the water in your pool appears cloudy and you notice sediment buildup on the bottom, and adding clarifiers and shock doesn’t solve the issue, you likely have hard water. Test the water to determine the calcium level. It should read between 155 and 400 parts per million (ppm); aim for about 275 ppm for the most balanced water. 

To achieve the ideal calcium level, pool professionals first balance the water’s pH, then the alkalinity, and finally the calcium. 

The Best Ways to Reduce Your Swimming Pool Water Hardness Level

If testing reveals the pool water’s hardness is over 400 ppm, you need to know how to reduce calcium hardness in a pool before adding more pool chemicals. You have three options. 

Add Fresh Water 

The easiest way to reduce the calcium level in the pool is to drain about a quarter of the water and add fresh water. If you aren’t sure how much water to remove, check with a pool professional. They can estimate how much water to drain to restore calcium balance without wasting water. 

Once you drain water from the pool, using either a siphon or the filter’s backwash setting, replace it with fresh water. Wait at least six hours for fresh water to mix with the existing water, then test the calcium again. 

Add a Flocculant

Using a flocculant before draining and replacing the water can help reduce calcium hardness in a swimming pool with a water hardness significantly higher than 400 ppm.

Flocculant is an additive that removes free-floating calcium (undissolved calcium) from the pool water. After adding the flocculant to the water and vacuuming the sides and bottom of the pool to remove the remaining calcium carbonate particles, backwash the filter. Drain and replace the water as described above. 

Add Acid 

Adding muriatic acid or dry acid to the pool water does not reduce the calcium hardness. However, it can help balance the water and control the hardness to make pool chemicals more effective. Because improper use can cause corrosion, talk to a pool professional about how to balance the water first

Let Classic Marcite Balance Your Pool Water

If you’re still unsure how to reduce calcium hardness in a pool or don’t feel comfortable doing it yourself, let the professionals from Classic Marcite help. Contact your nearest Florida location for services to eliminate pool algae and restore your pool to a refreshing oasis. 

Now Serving Black Hammock

We’re excited to announce that Classic Marcite now extends its pool maintenance and renovation services to the Black Hammock area. Residents in Apopka can now rely on our expert team for efficient and professional pool care, including the crucial task of changing the sand in your pool filter. Trust us to keep your pool in pristine condition.

About Mike Folta
Mike Folta has served the clients of Classic Marcite for more than 15 years. He has 20+ years in the pool industry servicing large hotels and theme parks in the Greater Orlando area, as well as expertly turning backyard pools into an island oasis.