As soon as temperatures drop, many people ask, “Can algae bloom in cold swimming pool water?” The simple answer to this question is yes! At this time of year, when the temperature drops, it doesn’t take much for your pool water to get much colder. When this happens many people feel that just dropping a chlorine tab in the floater is enough but trust us when we say, algae can and will bloom in cold swimming pool water. Even though you can use less chlorine and you can shorten your filter run times, you will still need to do a variety of things to keep your pool water blue and looking great. We hope this blog post helps to inform you on how you should take care of your swimming pool during fall and winter.
Just this past week, we were called out to a potential new customer’s house because even though they had 4 parts per million (ppm) chlorine and 7.4 pH they noticed algae on the sides of the pool, steps and around the light. Even though they were brushing the swimming pool and the water chemistry was right, it didn’t take us long to figure out why they had algae blooms. First of all, it was an 18,000-gallon swimming pool and they were only running their filter for 3 hours a night! This is way too short of run times. To get proper filtration you would need at least 6-8 hours minimum during the winter time and 10 hours during the summer. Next, their pool sweep wasn’t working because they had a majority of circulation going through the main drain and not the skimmer. Typically, you will want about 75% through the skimmer and 25% main drain. Since the pool sweep wasn’t working, it allowed dirt and debris to stick to the walls and algae built up.
After we made these changes, we received a phone call from them saying all the algae were gone and their pool looks great. This isn’t an uncommon problem. Too many people feel that they don’t need to do anything during the winter time but pools still need to be maintained both chemically and cleaned regularly. The only thing that should change should be using less chlorine and running your filter for less time. As far and brushing and removing debris, this still needs to happen regularly to prevent flow issues into the pump and debris in the pool. If you should have any questions, please don’t hesitate to contact us today!