Do Pools Need More Chlorine When It's Hot? Chlorine is a necessity for keeping your pool clean, free of bacteria, algae and viruses. Without it, your pool water can become murky, green, and even unsafe. However, too much also leads to trouble. To keep pool water safe and clean, chlorine should be maintained within a specific range. Too much chlorine can irritate the skin, eyes, and even lungs, while too little leaves you with a potentially unhealthy pool. What's more, chemical needs change depending on the time of year, since heat and UV rays affect chlorine. To maintain the proper balance, consider the following factors.
What Is Chlorine Demand?
Pool service technicians measure two types of chlorine: combined chlorine and free chlorine.
- Combined chlorine is the fraction of the chlorine that has reacted with organic matter, such as ammonia and nitrogen compounds and is, essentially, tied (“combined”) up. When your pool smells like chlorine, generally it is not because there is too much chlorine in the water but rather due to chloramines, the chemical compounds that result when chlorine meets organic material.
- Free chlorine is the fraction of the chlorine that hasn't yet reacted with organic matter; it is still able to disinfect the water.
High levels of combined chlorine indicate that there are too many foreign particulates in your pool water and free chlorine is the chlorine that needs to be replenished. It is important to remember that things like heat, increased bather load, and rain or wash-ins increase your chlorine demand.
How Do Heat and Light Affect Chlorine?
Free chlorine isn't just lost when it interacts with organic matter; it is lost when it interacts with sunlight as well. Chlorine forms hypochlorite ions in water, which break apart when hit by ultraviolet radiation, releasing chlorine gas into the atmosphere. The light from the sun can reduce pool chlorination by 90 percent in just a few hours. This is why many pool service technicians add a stabilized chlorine and use a chlorine stabilizer when necessary to maintain the conditioner levels.
Temperature also has an effect on chlorine, as some bacteria and organisms grow better in warmer environments. When temperatures increase, it uses up free chlorine more quickly, potentially turning your pool into a swamp.
Rule of Thumb: For every 10-degree Fahrenheit (6 degree Celsius) rise in temperature above 80 degrees Fahrenheit (26 degrees Celsius), you should add as much as 50% more chlorine to your pool water to maintain appropriate levels of free chlorine. This is especially true for those hot tubs that are not always covered, as they tend to run warmer.
Adjusting to Meet Chlorine Demand
It can take more than a week for your pool to recover from an algae outbreak or sudden water cloudiness. Here are a few things to keep in mind to help avoid any loss in the use of your pool:
- Test Water Frequently: When conditions that require more chlorine arise, you will be able to see your sanitizer disappearing when you test the water. You don't have to be a certified technician or water chemist to be able to test and know the condition of your pool water. Purchase some dip-strips to easily test your water and take care of any algae or cloudiness before it begins.
- Inform Service Providers of Pool Parties: While an increase in bathers definitely has an impact on your water's chemicals, you can minimize that impact. Informing your service technician of any plans you may have involving your pool allows your tech to take preventative steps and keep your pool clean and safe. Don’t wait until the last minute to let your service tech know about your upcoming pool party. They need to find time in their schedules to help you get your pool ready in addition to their regular commitments.
- Monitor the Pool after a Storm: Even light rainfall can dilute your water and offset the chemical balance of the pool. In addition, be on the lookout for anything that might have gotten washed into the pool, such as fertilizer or other lawn / plant chemicals, as well as leaves and debris blown in by the storm. Some of these may actually render your sanitizer or other chemicals ineffective, so be on the lookout.
- Prevention is Always Easier: It is easier to simply maintain well-balanced pool water than to clean cloudy or green water. Consistent testing and monitoring ensures that your water stays clean and safe to use, whereas ignoring it can leave you without a pool until you or your technician figure out exactly what is going on.
If you're looking for an easy way to ensure the water in your pool or hot tub stays balanced year-round, a pHin smart monitor constantly analyzes the water and automatically sends exactly what you need to keep your pool and hot tub healthy. Do you need someone to service your equipment? Pool Service on Demand connects you to local, qualified pool techs.