Calcium scaling… it can be an unsightly and annoying problem in your swimming pool. We wrote previously about how to remove calcium scaling manually. Another way to tackle this pesky problem is through the creative application of water chemistry. But first, a little background.
About Calcium Scaling
If you’re not familiar with it, calcium scaling shows up in a pool as a white film on tile and other pool surfaces. You’ll notice it right above the waterline. It can also manifest as what appears to be a white powder that accumulates on the pool floor. What’s more, over time, calcium buildup in pool equipment like your heater can decrease its effectiveness and ultimately require that the unit be replaced. So, getting calcium scaling under control is about more than just aesthetics!
Calcium is a mineral that is naturally present in water. “Scaling” occurs when the water chemistry changes in a way that allows the mineral to “come out of solution,” meaning that it is no longer dissolved in the water and has returned to its solid form as tiny particles.
As you would expect, one of the factors in how likely a pool is to develop scaling is the calcium content in the water, which can vary based on the water source. For example, water pulled from Lake Michigan for the many communities that surround it is very low in calcium. Water pumped from wells in areas where limestone is present, on the other hand, can have a very high calcium content.
Removing and Preventing Scaling through Simple Science
Removing scaling manually takes a significant amount of time and effort. And changing your water source is difficult and/or expensive. (Some people do truck in low-calcium water, but it costs a pretty penny!) So, using chemistry to your advantage can be a great way to go. How do you do that? Simply bringing your pH and total alkalinity to the proper levels will slowly start to correct the scaling problem.
However, some people want more rapid results. When used carefully, a strategy for a faster fix is to temporarily lower the pH in a pool to around 6.8 for a day or two to make the water slightly acidic. This can bring the calcium back into solution quickly, pulling it off of the pool surfaces, out of the heater, etc. You can also give the walls and floor some quick attention with a soft-bristle brush to speed the process along. The advantage to this approach is that instead of hours of scrubbing or weeks of waiting, you simply have to make an adjustment to your water balance and let chemistry do the work.
Be sure to use caution with this approach though. Letting your water get too acidic or leaving it in an acidic state for too long can damage pool equipment. Once the scaling is gone, it’s important to get the pH and total alkalinity levels back to normal right away. Then, the key to keeping scaling from coming back is ensuring those levels remain where they should be by checking the chemistry weekly and making minor adjustments as needed. Also, if you have a high calcium content in your water, you should consider using chlorine that is not calcium-based. Instead, try sodium- or lithium-based alternatives.
Look Before You Leap
Before taking any action to address calcium scaling, you should contact us or your local Latham dealer. We can talk with you about the source water in your area and the best way or ways to keep your pool looking great!