10 Easy Tips to Winterize Pools, Spas and Hot Tubs

Sure, the official beginning of fall is still a few weeks off, but it’s still autumn in all the ways that count. And if you’re anything like these fall lovers, you’re too busy contemplating your next pumpkin-spiced bev to be sad about bidding your pool farewell for another season.

That said, closing a pool is no enviable task. Cleaning and balancing the chemicals, protecting against algae and freezing, managing the equipment and blowing out the plumbing lines—it’s a lot to fit into your fall schedule! That’s why we created this list of tips to help you get it right, right from the start. After all, the sooner you say sayonara to your pool, the sooner the real fall fun can begin.

beach ball in a pool

Make Sure the Weather Is Right

An unexpected Indian summer can encourage algae growth, creating a big headache when you open back up in spring. Instead, wait until the water temperature measures about 65 degrees Fahrenheit. You’ll save yourself a lot of work next year!

Give Your Pool Extra Algaecide in the Late Fall

Today’s weather is pretty unpredictable (thanks, global warming!), so you may get some unseasonably warm temperatures even if you wait. That’s why it makes sense to apply an extra dose of algaecide and chlorine in the late fall—or even the early winter—to outthwart warm-weather algae.

Closing is a Process, So Take Some Time to Prep

Much as you’d like to have your pool closing over and done with, you should really break it up into a couple steps throughout the span of a week. Specifically, take some time to vacuum your pool and give it one last thorough cleaning. Then, about a week before you’re planning to close your pool, add a phosphate remover, which helps limit the growth of algae in the coming months.

But Before You Do That, Balance the pH

Balancing your pool’s pH levels are an integral part of your closing process, even if you’re hiring a pool service to close it down for you. In fact, all chemicals should be balanced the day you begin closing, so use water treatments to manage the levels, if necessary. For the record, “balanced” means a pH between 7.2 and 7.6, alkalinity of between 80 and 120 parts per million (ppm), and calcium levels between 180 and 200 ppm. Do this first and your pool will survive the winter with ease!

Don’t Shock and Add Algaecide at the Same Time

Most people consider shock to be an absolutely necessary step in the closing process, but you shouldn’t do it when you’re hitting the water with a dose of algaecide. All that extra chlorine will break up the polymer chains in the algaecide, which basically means you poured it all in for nothing. Instead, shock the pool about four to seven days before you close, then add algaecide right before you cover it.

Never Drain Your Pool All the Way

You probably already know that freezes present a very real danger to your pool. What you might not know is that draining your pool can accelerate those problems. In fact, experts say you should always leave some water in there, particularly if you live in a warmer climate or have an above-ground pool. The pressure from freezing can pop the pool out of place or damage the lining, so it’s best not to drain it to protect pool surfaces.

But Do Completely Drain Plumbing Lines

However, your plumbing will suffer enormously if there’s any water left in the lines. Use a pool blower or industrial-grade shop vac to blow out the water, then add a swimming pool antifreeze to protect your plumbing during freezing temperatures.

Consider Adding a “Winter Pill”

Some professionals advise using a “winter pill,” a floating ball of enzymes and treatments that work to break down oils and prevent scum from forming, all winter long. The only caveat to this is that you’ll have to skip your final shock treatment—or use a non-chlorinated alternative—because the high chlorine levels can disrupt the enzymes’ functioning.

And an Air Pillow

Another floating fix, an air pillow takes some of the pressure off your pool—by that, we mean it literally absorbs some of the pressure from the ice forming in your pool, protecting the surfaces. Place the air pillow under the cover before you close up and let it do its thing all winter long.

If All Else Fails, Hire a Pro

Of course, the easiest way to get something done is to hand it over to the pros! Professional contractors will drain your pool and connected plumbing lines to prevent freezing and algae growth. They can also take special measures to prevent freezing, such as adding antifreeze to the plumbing, or using a winterizing air pillow and enzyme treatments. After all, there’s nothing like having a pro on hand to handle any problems that arise. And that means more time sipping cider and relaxing under a cuddly blanket—a definite fall win!