What do you need to do to your pool after it rains? Spring and summer can bring about heavy rainfall and storms that affect your pool water. With enough rainfall, even a previously well-balanced, well-maintained pool can take a quick turn toward algae, dullness, cloudiness or swimmer discomfort. 

Good news: The right combination of HTH Pool Care products can bring your pool back to sparkling blue.  


Don’t let summer storms put a damper on your fun. Follow these simple tips after the storms pass and you’ll be cannonballing into crystal clear water in no time. Here’s what to do after heavy rain to make sure your pool stays swim-ready: 

Test Your Water

Heavy rains can dilute the chemicals you’ve added to your pool water. After a storm or lengthy rain, you want to check on your water balance, stabilizer and sanitizer levels. Check your water balance, stabilizer and sanitizer levels with an HTH® 6-Way Test Kit or HTH® Multipurpose 6-Way Test Strips. If you’re using test strips, you can compare the colors on the test strip to the color panel on the side of the canister or you can use the FREE HTH Textstrip program: Just take a photo of your test strip and text it to 484-123, and you’ll get a text message with your balancer levels and personalized instructions 

dirty pool after storm

Water Balance and Chemistry

Did you know rainwater has its own water chemistry? That’s why significant rainfall could raise or lower your pool water’s pH and Total Alkalinity levels. Your test strip results will help you understand what your pool needs. You may need HTH® pH DownHTH® Alkalinity Up, or HTH pH Up balancers to get your pool water back to sparkling clear blue. 

Clean and Treat

Rainwater that washes or falls straight into the pool water or that falls off of tree branches can introduce algae and other contaminants into your pool. These contaminants can quickly use up your sanitizer. Add an HTH® shock treatment after the rain has passed to break down the contaminants and keep your pool water clear for the next swim day.  

Following a Flood

If your pool has been affected by recent flooding, special measures are necessary to restore the water quality to a swimmable condition. If you have any questions about how to get your pool back to blue, call our customer care team at 866-484-7665 for the information you need.