Pool Chemicals: Understanding Chlorine & pH

Now that we have talked about filters and skimmers, we can finally move on to chemicals and water balancing. Of course, you can take a sample of water up to your local pool store, and they will sell you a few hundred dollars of chemicals to add. Is that always the wrong way to get your pool clean? Not all the time. But for the most part, you can keep your pool clean, clear, and blue by just following a few simple water balancing tips.


3-5 part per million (or PPM) is what most pool guys will tell you is the accepted level of chlorine to have in your pool. But, at some point during the summer, you'll be calling those same pool guys to get your pool to turn from green back to blue.

Pools that we manage are kept at almost twice that level (between 6-10 PPM). Now, you might think that raising the level of chlorine to twice the recommended level is going to cost you more money in chemicals, but that's simply not true.

Think of it this way—the amount of bacteria in your pool is going to require X amount of chlorine to be added. In addition, the sun is going to consume some of the chlorine as well. So what happens to the rest of the unused chlorine? It stays in the water waiting for more bacteria to kill. In other words, if you keep your chlorine at 10 PPM, it's going to use the same amount to kill the bacteria as it would at 5 PPM.

Using a higher level of chlorine ensures there's always enough chlorine to kill whatever bacteria is in the pool. Once the desired level is achieved, it won’t be hard to keep the chlorine at the desired level.


pH is equally important to monitor. Believe it or not, itchy eyes and red skin don’t come from too much or lack of chlorine, like some think. Rather, it comes from pH being too high or low. In addition, when pH falls out of the 7.2-7.8 range, it dramatically decreases the effectiveness of the chlorine.

Most pools over the course of the season have a tendency to have a low pH. Chlorine, sun tanning lotions, urine, and people's skin, all of which enter a pool pretty much daily in the summer, can cause the water's pH to lower. That means you will need to raise the pH.

Now, you can run to the pool supply store, and they will sell you some expensive pH increaser. This will immediately increase your pH levels but also cause your water to become cloudy. The best way to increase your pH is to add freshwater to your swimming pool.

In the Omaha area, most of our water comes out of the sink around 8.0-8.2, depending on where you're located. You can test your tap water to be sure. Adding freshwater will not only increase your pH, but will actually help make your water clearer. Plus, you can cool down your lukewarm pool by adding cool freshwater.

Finally, when purchasing chemicals, especially if in a Walmart, Lowe's, Home Depot, or Menards, be sure to check labels. Many times, larger retailers will put clarifier and algaecide on sale. You’ll see a giant gallon jug of algaecide that normally would cost $30 or more on sale for less than $10. But if your read the label, you’ll quickly figure out why the bigger container is selling so cheaply.

The label will list the chemicals in the bottle, and then it will tell you the % of inert (or basically unused) materials. In many cases, this “inert” material is water. So with a big gallon jug of algaecide, you may only be getting 10-25% of product, and the rest is just water and other inactive materials. The same goes for clarifier and chlorine. So, if you're thinking that the deal is too good to be true…it probably is.

Call us with any questions or issues, and we will be happy to help.

Tyler’s Pool and Home Care provides professional lawn care, pool care, and snow removal services for Omaha-area homes and businesses. Contact us today at 402-590-6860 or tylerspoolandhomecare@gmail.com.

Comments are closed.