8 Essential Supplies to Winterize an Above Ground Pool

As autumn leaves begin to fall, above ground pool owners face the inevitable task of closing down their backyard oasis for the freezing winter months. Skipping the proper winterization steps can lead to cracked plumbing, ripped liners, and a green swamp come spring. Investing in the right seasonal gear now ensures that your pool remains protected from ice damage and reopens with minimal effort next season.

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What to Do Before You Begin the Closing Process

Before reaching for any winterizing chemicals or pool covers, a thorough deep clean is absolutely mandatory. Debris left in the pool over the winter decays, staining the liner and consuming the protective winter chemicals rapidly. Vacuum the floor, brush the walls, and skim the surface until the water is completely free of organic matter.

Next, clean out the skimmer basket and pump strainer pot to prevent trapped debris from rotting over the off-season. You also need to backwash your sand filter or thoroughly rinse your cartridge filter to ensure no residual grime hardens inside the system. Taking these physical cleaning steps first lays the groundwork for a successful winter chemical treatment.

Pool Cover – Robelle 3524-4 Premium Winter Cover

A high-quality pool cover acts as the primary shield against harsh winter elements, keeping out leaves, dirt, snow, and sunlight. Without a solid cover, UV rays will deplete your winter chemicals, while organic debris will turn your pool water into an algae-filled swamp. A reliable cover must withstand heavy wind, freezing temperatures, and the weight of accumulated precipitation.

The Robelle 3524-4 Premium Winter Cover stands out due to its heavy-duty polyethylene construction and a dense 12×12 scrim count. This tight weave prevents water from seeping through while resisting tears from falling branches or wind shear. The cover features a 4-foot overlap, providing plenty of extra material to secure over the top rail without placing excessive tension on your pool walls.

• Material: Heavy-duty polyethylene
• Scrim Count: 12 x 12 (high density)
• Overlap: 4 feet of extra material
• Included Accessories: Vinyl-coated cable and metal winch

When selecting your size, always measure the actual pool dimensions and ensure the overlap accommodates your specific top rail width. This cover includes a vinyl-coated cable and a heavy-duty winch system, which are crucial for locking down the perimeter against strong winter winds. Keep in mind that while it comes with a securing cable, adding extra hold-down accessories is wise in high-wind regions.

This cover is ideal for backyard owners in regions with heavy snowfall and freezing temperatures who need reliable, multi-season protection. It is not the right choice for pool owners looking for a lightweight, temporary tarp that only lasts a single season.

Air Pillow – Robelle Double Chamber Air Pillow

Above ground pool walls can buckle under the immense pressure of expanding ice during a deep freeze. An air pillow sits in the center of the pool under the cover, acting as an expansion cushion that absorbs the freezing water’s lateral pressure. By forcing the ice to expand inward against the soft pillow rather than outward against your pool walls, you prevent costly structural damage.

The Robelle Double Chamber Air Pillow is engineered to withstand the extreme pressure of freezing conditions without popping. It is constructed from heavy-duty 16-gauge vinyl and features two independent chambers for added reliability. If one chamber suffers a slow leak during a brutal winter storm, the second chamber remains inflated to protect your pool structure.

• Material: 16-gauge vinyl
• Chamber Design: Dual-chamber safety backup
• Inflation valve: Push-in leak-proof valves
• Primary function: Lateral ice expansion absorption

Fill this pillow to only 60% to 70% of its total capacity to allow room for compression when ice forms. Secure it in the exact center of the pool using ropes tied to the pool walls before laying the cover down. Pulling the cover too tight over a fully inflated pillow can strain the seams, leading to premature deflation.

This heavy-duty pillow is a necessity for pool owners in northern climates where sustained freezing temperatures create thick ice sheets. If you live in a mild climate where pool water never freezes, you can skip this accessory entirely.

Chemical Kit – InTheSwim Ultimate Winter Closing Kit

Closing a pool with balanced water is only half the battle; you also need slow-releasing chemicals to fight algae and staining over several months of dormancy. A specialized chemical kit keeps the water sanitized, prevents mineral scaling, and ensures you do not open to a black or green pool in spring. These pre-measured kits remove the guesswork, saving hours of chemical measuring during a chilly autumn afternoon.

The InTheSwim Ultimate Winter Closing Kit delivers a comprehensive defense system with its multi-step chemical approach. It contains a powerful winterizer algaecide, non-chlorine shock, a metal rust preventative, and a unique slow-release chemical floater. This chemical floater slowly dispenses sanitizer throughout the winter, maintaining water quality even as temperatures fluctuate.

• Pool Capacity Compatibility: Up to 35,000 gallons (varies by kit size)
• Included Components: Winterizer algaecide, metal free, winter shock, slow-release floater
• Chemical Type: Non-chlorine oxidizing shock (liner safe)
• Algae Protection: Multi-month preventative formula

These kits are sized based on total pool volume, so calculate your gallon capacity accurately before purchasing. The chemicals are formulated to work best in cool water, so wait to apply them until your pool water temperature drops below 60 degrees Fahrenheit. Using these chemicals too early when the water is still warm will deplete their active sanitizing power too quickly.

This kit is perfect for busy pool owners who want a simple, highly effective chemical regimen packaged in a single box. It is not ideal for those who prefer to custom-blend their own winter chemicals or have specialized alternative sanitation systems that require specific chemical exclusions.

Cover Pump – Wayne WAPC250 Automatic Pool Pump

Standing water on top of a pool cover is a recipe for disaster, as it adds immense weight and attracts breeding mosquitoes. A dedicated cover pump removes this accumulated rainwater and melted snow, preventing your winter cover from slipping into the pool. Without a pump, you risk tearing the cover seams and dumping dirty surface water back into your clean pool water.

The Wayne WAPC250 Automatic Pool Pump is a submersible utility pump that features smart, oil-free sensing technology. It automatically turns on when water levels reach 2.1 inches and shuts off when the water drops to 0.75 inches, operating completely unattended. With a flow rate of up to 3,000 gallons per hour, it clears heavy rainfall from your cover in minutes.

• Flow Rate: Up to 3,000 gallons per hour
• Activation Threshold: Turns on at 2.1″, off at 0.75″
• Motor Protection: Freeze protection auto-shutoff
• Base Design: Strainer base filters out leaves and debris

The pump features an integrated freeze protection sensor that prevents the motor from running if the water freezes, protecting the internal components from burnout. Ensure the discharge hose is run to a safe drainage area away from your pool’s foundation to prevent erosion. Periodically clear any leaves or debris from the intake screen to maintain optimal water flow.

This automatic pump is an absolute must-have for owners in areas with high winter precipitation who cannot manually monitor their pool cover daily. It is not necessary for pool owners in arid, desert climates where winter rainfall is virtually non-existent.

Skimmer Guard – The Gizzmo Skimmer Expansion Plug

Water entering your skimmer faceplate can freeze and expand, cracking the delicate plastic housing and causing devastating leaks. A skimmer guard acts as a sacrificial expansion plug that absorbs this destructive pressure inside the skimmer throat. It seals off the skimmer plumbing line while offering a hollow chamber that collapses safely when water freezes around it.

The Gizzmo Skimmer Expansion Plug is the industry standard for protecting above-ground skimmer boxes from freeze damage. It features heavy-duty molded plastic construction with a built-in 1.5-inch tapered thread that screws directly into the bottom of the skimmer. The hollow, compressible design is engineered to deform under ice pressure, absorbing the force that would otherwise shatter your skimmer wall.

• Material: Heavy-duty molded plastic
• Thread Size: 1.5-inch tapered pipe threads
• Style: Standard (9-inch length for standard skimmers)
• Primary benefit: Absorbs expansion to prevent skimmer wall cracking

Wrap the threaded end with Teflon tape before screwing it in to create an airtight seal that prevents water from seeping down into the underground pipes. Ensure you select the correct length for your skimmer basket depth to ensure the expansion chamber sits fully within the freezing zone. Always store this plug in a safe place during the summer so the threads do not get damaged or dirty.

This tool is essential for anyone winterizing a pool in freezing regions who does not want to drain their pool water below the skimmer mouth. It is not needed if you plan to completely remove your skimmer box and store it indoors for the winter season.

Cover Wrap – Blue Torrent Pool Cover Seal Wrap

Strong winter winds can easily get under the edges of an above ground pool cover, flapping the material and causing devastating tears. Once the wind gets a foothold, it can lift the cover entirely, exposing your pool to dirt and dumping accumulated debris inside. A specialized cover wrap acts like heavy-duty shrink wrap, sealing the cover’s outer perimeter tightly against the pool wall.

The Blue Torrent Pool Cover Seal Wrap is a high-performance, UV-stabilized stretch film designed specifically to withstand harsh outdoor conditions. It features a unique blend of resins that allow it to stretch tightly around the top edge of your pool while resisting puncture. Wrapping this around the pool multiple times creates an airtight barrier that keeps both wind and debris from penetrating the cover’s edge.

• Material: UV-stabilized stretch film
• Width: 80 gauge strength, standard width rolls
• Application: Clings directly to metal, resin, and vinyl cover materials
• Weather Resistance: Rated for sub-zero temperatures and high UV exposure

For the best results, apply this wrap by walking around the pool perimeter three to four times, overlapping each layer slightly. Ensure the pool wall is clean and dry before application to maximize the wrap’s grip and prevent slippage. Do not pull the wrap too tight around sharp metal edges, as this can cause the film to tear prematurely.

This wrap is highly recommended for backyard pool owners in open, windy areas who struggle with shifting or lifting covers during winter storms. It is less critical for pools heavily shielded by surrounding fences or windbreaks that naturally block strong gusts.

Expansion Plug – Aladdin Winterizing Rubber Plug

Water left inside return lines and plumbing can freeze, expand, and rupture the hoses or plastic fittings of your filtration system. An expansion plug seals off these pipe openings from the inside of the pool, preventing water from re-entering the plumbing lines after they have been blown out. It provides a reliable, watertight seal that stands up to freezing temperatures throughout the winter.

The Aladdin Winterizing Rubber Plug features premium, heavy-duty rubber designed to resist chemical degradation and freezing temperatures. It is equipped with a large nylon wing nut and non-corrosive stainless steel bolts that compress the rubber sleeve when tightened. This expansion action creates a tight, custom seal inside your return fittings that will not slip under pressure.

• Material: Premium chemical-resistant rubber
• Hardware: Non-corrosive stainless steel bolts and nylon wing nuts
• Sizing Options: Available in sizes 00 through 14 (standard pool returns use size 9 to 11)
• Seal Type: Compression expansion fit

Always clean the inside of the return fitting to remove any algae or slime before inserting the plug to ensure a perfect grip. Tighten the wing nut until you feel a firm resistance, but avoid over-tightening, which can distort the rubber or crack plastic return threads. Be sure to match the plug size to your specific return line diameter, which is typically 1.5 inches for standard above ground pools.

This plug is a critical item for any pool owner who leaves their pool plumbing intact over the winter and needs to seal the return lines. It is not necessary if your above ground pool setup allows you to completely disconnect and store all hoses and return fittings indoors.

Cover Clips – InTheSwim Above Ground Cover Clips

While cables and winches hold the cover’s perimeter, they often allow the cover to flap against the pool’s metal top rail in high winds. This friction can wear holes through the cover material and scratch the pool frame, leading to premature rusting. Cover clips lock the cover directly to the pool’s metal top rail, eliminating movement and reinforcing the cover’s grip.

InTheSwim Above Ground Cover Clips are crafted from durable, weather-resistant plastic designed to withstand sub-zero temperatures without cracking. They are shaped to snap securely over the pool’s top rail, gripping the cover material tightly without pinching or tearing it. These clips provide localized tension, ensuring that even violent wind gusts cannot lift the cover edges.

• Material: High-density, freeze-resistant plastic
• Clip Length: 5 inches per clip
• Pack Quantities: Available in packs of 20, 30, or 40
• Compatibility: Standard metal top rails

For maximum wind protection, space these clips evenly around the pool, using at least two clips per top rail section. Keep in mind that these clips are designed for standard metal top rails and may not stretch over extra-wide resin rails. Always measure your top rail thickness before buying to ensure the clip jaw can accommodate the width.

These clips are perfect for pool owners looking for an inexpensive, highly effective way to stabilize their winter cover against strong winter winds. They are not suitable for pools with oversized, decorative top rails that exceed standard metal rail dimensions.

How to Properly Balance Your Water Before Closing

Balancing your pool chemistry before closing is the single most important factor in preventing scale, corrosion, and algae growth during the winter. If your pH or alkalinity is off, your winter chemicals will not perform effectively, leaving your liner vulnerable to staining. Aim to balance your water several days before your planned closing date to allow the chemicals to circulate thoroughly.

Focus on adjusting your pH to between 7.2 and 7.6, and your total alkalinity to between 80 and 120 ppm. Calcium hardness should also be maintained between 175 and 250 ppm to protect the vinyl liner from becoming brittle in cold temperatures. Run your filtration system for at least 24 hours after making these adjustments to ensure the entire water body is perfectly uniform.

Managing Snow and Ice Accumulation on the Cover

Heavy snow and ice accumulation can put immense physical strain on your pool cover, cable system, and pool walls. If left unchecked, the sheer weight of a heavy snowstorm can pull the cover into the pool or buckle the frame walls. Regularly monitoring your cover after major winter storms is essential to prevent catastrophic structural failure.

Never use a sharp shovel or rake to remove snow from the cover, as these tools can easily puncture the vinyl or fabric. Instead, use a soft-bristled broom or a specialized roof rake with a protective head to gently push snow off the edges. If the snow has frozen into a solid sheet of ice, leave it alone until it melts naturally, and then use your cover pump to drain the liquid.

Spring Reopening Secrets for a Crystal Clear Pool

The secret to an easy spring opening begins in the final weeks of winter by closely monitoring your pool cover water. As soon as the ice melts, pump off any standing water and remove any heavy leaf accumulation before taking the cover off. This prevents dirty water from spilling into your clean pool when you pull the cover away.

When removing the cover, work with a partner to carefully fold it accordion-style to trap any remaining debris inside the folds. Once the cover is off, clean it immediately with a cover cleaner, let it dry completely in the sun, and store it in a sealed container to keep pests out. Reconnect your filtration system, top off the water, and shock the pool immediately to jumpstart your summer swimming season.

Conclusion

Taking the time to winterize your above ground pool with the right supplies saves you from expensive repairs and endless spring cleaning. By protecting your structure and balancing your water now, you ensure a stress-free transition when warm weather returns. Equip your backyard oasis with these essential tools and enjoy peace of mind all winter long.