How to Close Your Above Ground Pool for the Season—The Right Way

These things can happen much too fast. You just got used to stretching out by the pool and seeing the world through clear inflatables and black shades, right? Unfortunately, all good things come to an end. And unless you live in a sunny, tropical place, where you might be able to expect to swim on Christmas Day—which, by the way, means you have my envy—you’ll need to close your above-ground pool for the winter. I’ll explain why you should close your pool, when to do it, what you’ll need, and finally, how to close your above-ground pool—the right way. Get ready to make pool season next year all the easier to cannonball into, and save yourself some serious time and money, too.

Why Close for the Winter?

Well, maybe you don’t need to close your pool at all. If you’re one of those incredibly lucky pool owners who happen to live somewhere with really mild winters—that is, without frost, snow, and the teeth-chattering cold that comes with them—then you’re probably good to leave your pool open. Just keep in mind that keeping your pool open for the winter also means you’ll be cleaning out debris and adding chemicals, which takes time, and running your pool pump and greater circulation system, which will be a major cost. If you’re not swimming, that just isn’t necessary—even if you do have a seriously cost-saving variable speed pump.

If you choose to close your pool, you’d better do it right—the last thing you want on the first day of swim season is to open your pool cover to a disgusting, cloudy combination of debris, algae, grime, even white mold. If you close your pool the right way, it’ll take even less effort (and money) to open it up again in the spring.

Timing, Timing, Timing

This one is a win-win, and you’ll be surprised you didn’t think of it yourself: if your temperatures typically stay below 65 degrees, leave your pool open until the weather cools down below that point. That way, you can treat and use your pool as usual right up until it’s time to say goodbye for a few months—and it’ll help keep your pool algae-free through the winter. Plus, that way you’re not rushing this process. As you’ll see, it’ll take over a day to really close your pool, since pool shock can only be added at dusk or night.

If during the winter you have a few warm days above 65 degrees, you can treat your water on those warm days to prevent algae and give yourself an advantage when you open your pool next season. Trust me, the work you’re doing now far outweighs the work you’d have to do later if your pool goes totally untreated throughout the winter.

how to close your above ground pool for the winter

Get That Gear

Yeah, you’re going to want to be prepared for this. But don’t worry—whatever you have to stock up on this year, you’ll be able to use next year. Here’s what you’ll need:

- Above-ground pool winter cover

- Pool air pillow

- Above-ground pool skimmer cover

- Cover winch and cable

- Cover clips

- Expansion plugs

- Return line plugs

- Pool brush

- Pool vacuum or robotic cleaner

- Shop-Vac or air compressor

- Tools for removing pool accessories, like ladders

- Winter pool cover pump

Check Those Chemicals

Now that you’re geared up, it’s time to check out your chemical supply. If you don’t have any of these—with the exception of cyanuric acid unless you have unstabilized chlorine, antifreeze for pools if freezing is an issue for you, and pool enzymes, which are just plain optional—it’s time to get them. Here’s the full list: 

- Water test strips

- Chlorine or your choice of sanitizer

- pH increaser

- pH decreaser

- Alkalinity increaser

- Calcium hardness increaser

- Algaecide

- Pool shock

- Cyanuric acid

- Pool enzymes

- Pool-grade antifreeze

How to Close Your Pool for the Season—In Ten Steps

Okay, so you’ve got what you need. Now it’s time for the real work to begin. I won’t pretend that it’s easy to close your pool for the winter, but I can tell you that it’ll all be worth it in the spring. And once you’ve got this process down, it’ll come back to you faster and faster every year. Because as you know: when it comes to pool maintenance, you’re in this for the long haul. Better eat some protein for this first step.

 Step 1: Use Elbow Grease to Clean Your Pool

Bye bye, potential food for algae and mold. First, give your pool that usual skim with a net on a telescopic pole. Next, use a brush to scrape down the bottom and sides of your pool, especially trouble spots that are especially susceptible to these unsightly growths. This will both dislodge any microscopic spores that might bloom later if left alone and help your pool shock work extra hard in a few steps. My top recommended brush is the only one like it on the market, thanks to a patented 360 degree brush head perfect for getting trouble spots. Plus, it was developed by longtime pool servicers who were tired of aches and pains that resulted from brushing stairs and other corners.

Next, vacuum your pool floor with a reliable and heavy-duty model like the Blue Torrent MyBot Robotic Cleaner to pick up debris that might’ve settled on its surface. Since you can easily run this robotic cleaner without the back-straining force of a manual vacuum, feel free to sit poolside with a cold can for this step. That’s the life.

Step 2: Put Your Water to the Test

Skip this step, and “stewing” will take on a whole new meaning, apart from how you feel after a fight with your partner. While your pool is closed, it’ll be covered and largely safe from the elements, but rarely are winter covers foolproof. Plus, you won’t be running your circulation system eight hours a day, or however long you should be running your pump. So what you do now will give your water a serious leg up throughout the winter. 

If your sanitizer and other chemicals are properly balanced, your pool is all the more protected from corrosion, extreme clouding up, and becoming an overall murky mess that will cost big to fix. Love that idea? You’ll love this next step even more.

Step 3: Wave Summer Goodbye by Adding Winterizing Chemicals

Sure, balancing your chemicals before closing will sure help the water from becoming an actual swamp. But this isn’t any regular weekly maintenance, at least not for now. There are also some chemicals that could give your pool an extra boost. For example, pool enzymes can be added to your water to help attack any organic contaminants that might still be in your water. And if you live in a place that gets cold enough for your pipes to freeze, use a pool-grade antifreeze—not the toxic kind designed for cars.

I know, algaecide was also on the list of chemicals you need (that is, if you have an algae problem). We’ll get to that in this next step. Let’s carry on, yeah?

how to close your above ground pool for the winter

Step 4: Shock Your Pool—So There’s No Cause for Alarm Later

Just what you were looking for: a break. It’s time to shock your pool, but remember that you’ll need to do this at dusk or at night or the sun will burn it off before it has the chance to work. So shock your pool after sunset tonight, run your pool pump for eight hours, and get ready to do these next steps tomorrow.

If you currently have algae blooms that you’ve just brushed and vacuumed up, you can double or triple the amount of shock you use depending on the algae’s color. But no matter what, be sure you’re measuring out the right amount of shock for your pool size. This Super Premium and Fast-Acting Pool Shock comes in one-pound bags to keep dosing simple.

And if your pool is in fact at risk for algae, add one or two doses of algaecide after your shock is done doing its job. Despite its flashy name, algaecide is better at preventing algae than actually killing it. But don’t worry, that’s one of the many reasons we have another flashy-named tool: pool shock.

Step 5: Take Those Lines Down—and Dry Them Out

Okay, the last thing anyone wants is cracked pipes that need a total replacement. But whether or not you have to worry about freezing pipes in the winter, clearing and storing your pool lines will make them a lot easier to set up again in the spring.

Ready to make it happen? All you have to do is disconnect the lines, allow all the water still lodged in them to run out, then let them air dry outside—we don’t want any uninvited guests, like mold, to appear on pool opening day. Once they’re completely dry, store your pipes in a dry, shaded area. Oh, and word from the wise: don’t do this while your circulation system is on, or even connected to power. Nobody’s going for a mad scientist look.

Step 6: Skimmer Time

Now let’s keep this as non-confusing as possible. When pool experts refer to your “skimmer,” they’re talking about the rectangular plate (called the skimmer plate) that sits on the side of your pool, and the basket (called the skimmer basket) that usually connects to it and holds debris. To get your skimmer winterized, you’ll want to first empty out that basket. No way do you want those leaves and twigs and who-know-what-else sitting there for months. Ick.

As for the skimmer plate, you can decide whether or not to cover it. I recommend that you do, because otherwise you’ll need to drain your pool below the skimmer line. That’s never a breeze to do. Plus, if your water freezes it can cause permanent damage to the skimmer. If you’d rather not cover your skimmer since you have super mild winters and you’re good with draining some of your pool water, then that’s cool, too. 

Step 7: Give Your Pump and Filter a Leg Up

The summer might be vacation time for you, but the winter is when your pump takes some much needed time off. To take down your pump, remove all drain plugs from the pump and the filter. You’ll also want to remove the pump itself, the chlorinator, and all hoses. Store all drain plugs in the pump basket for easy locating next spring, and keep the pump, chlorinator, and hoses in a dry, shaded area indoors. A garage, for instance, is perfect for the task.

As you might know, your filter is a holding place for all the gunk that it can pick up from your water as it circulates through. Yeah, you’re going to want to drain them before storing them inside—no way do you want that stuff sitting for long.

If you have a sand filter, set your multiport valve to “winterize” and remove the drain plug at the bottom. Allow the filter to completely drain. If your valves has any other extras, like a sight glass or a bleeder valve, remove those, too. If your filter is too heavy to carry inside, it’ll be fine as it is: outside, with all drain plugs removed. 

For cartridge filters, just take the cartridge out, submerge it in water with pool filter cleaner, rinse it out, let it dry, and store it inside. You’ll want to leave the valves open on your filter throughout the winter.

For diatomaceous earth (DE) filters drain all water out of the pump and filter, and then rinse off the grids with a hose to remove excess DE. Again, leave the valves open on this one.

how to close your above ground pool for the winter

Step 8: Take Those Accessories (And More) Down

To make sure your pool is completely covered from debris and prevent unnecessary damage, you definitely want to remove any pool ladders, rails, and other accessories you have installed in your pool. (That’s one reason why you’ll want a pool ladder with easy installation and take down, like the Easy Pool Step Ladder for Above-Ground Pools.) This is also a great opportunity to give them a good rub down, then let them dry and store them in a safe spot until next pool season. Make sure all electronics are stored indoors for the winter.

Do you have a saltwater pool? Now is the time to remove your salt water chlorine generator, drain it, and store it. (Some have a “winter” setting, which will make this easier.) Plus, you can turn off all power and gas to your system. You won’t be needing them—and you’re about to love the bills that come in.

Step 9: Drain Part of Your Pool—Or Don’t

So you didn’t opt in for the skimmer cover and you’re expecting a tough winter, huh? Hey, you do you. Lowering your water level will help big time to prevent freezing damage, but don’t lower so much that your pool walls are extremely exposed and could crack. Just under the skimmer should do the trick.

All you have to do is lower the water level of your pool with a submersible pump. Be sure to watch it working, so you don’t accidentally remove too much water. That would be seriously, ah, draining.

Be sure to check with your local authorities about where that water you drain should go—especially since it’s just been chemically treated. The last thing you want is fees and environmental damage on your hands.

Step 10: Install a Winter Pillow & Cover

Who else is ready for a nap? Even your pool needs a pillow once a year—but don’t worry, you don’t need to sacrifice anything from your linen closet. If you live in a cold climate, you’ll want to place a pool air pillow, or ice compensator, under your winter cover. This will protect both the sides of the cover and the walls of your pool from pressure damage from the ice or snow that will soon sit on top of your pool. Don’t live in a cold climate? Well, a pillow will still make clean up tons easier next spring. After all, it keeps water and debris from pooling in the center of your pool.

To install the pillow, blow it up and place it in the middle of your pool. If you’re into perfectionism, get a pillow that has built-in grommets that allow you to secure all four corners to your pool and keep it perfectly center. Just make sure that you inflate the air pillow only to around half of its capacity. Otherwise, it might pop mid-season—and you’ll have to deal with some seriously cold water to replace it. Better yet, seal off the seams and valves with duct tape after you inflate the pillow. This will keep it as resilient as possible. Hey, we all need a little extra strength to get through the cold months. 

Next, it’s time to put your winter cover on. This will keep your pool water safe from debris and contaminants, and keep the chemicals in your water without getting seriously diluted by rain, snow, or whatever else might come your pool’s way. Most covers can even make sure all gaps are gone, so no worries about skimming out leaves—though you will want to check on the cover periodically. Just make sure that you secure it according to the manufacturer’s instructions, and not with heavy objects that could fall into—and damage—your pool.

Didn’t go with a pillow this year? Once it rains or snows, you’ll find that the center of the cover will eventually have a big puddle of water. This is normal, but don’t intervene and it will eventually get so heavy that it sinks into your pool—bringing all that nasty water and debris in, which undermines a lot of the work we just did to keep the first day of next year’s pool season as happy as it should be. My recommendation is a durable and heavy-duty cover pump like the Brute Force 1250 GPH Pool Cover Pump. As one owner noted, it “saves so much time.” That’s what I’m talking about.

how to close your above ground pool for the winter

Look Forward to Next Year!

Well, now it’s done. Another great season has come to a close: our bathing suits are back to the back of the closet, our floaties are properly deflated, and now we have something to look forward to. Since you took the time to close your pool the right way, the first day of next year’s pool season is going to be a splash. Until then, it’s all about gingerbread, snowmen, and very light energy bills. Enjoy.

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