8 Essential Steps and Tools for Winterizing an Above Ground Pool

As the summer heat fades and autumn leaves begin to drift into the backyard, pool owners face the inevitable transition to the offseason. Neglecting proper closing procedures can turn a pristine swimming oasis into a costly, cracked nightmare come spring. Securing the right tools and following a systematic winterization process ensures that the pool survives the brutal freeze-thaw cycles unscathed and ready for next year’s first warm day.

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Why Winterizing Your Above Ground Pool Matters

Above ground pools are uniquely vulnerable to cold weather because their walls are entirely exposed to the elements. When water freezes, it expands by about nine percent, exerting massive outward pressure that can easily bow metal frames, split vinyl liners, or crack expensive plastic fittings. Properly winterizing mitigates this destructive force by preparing the water chemistry and physical structure to withstand sub-zero temperatures.

Beyond structural protection, closing a pool correctly saves hours of backbreaking labor and hundreds of dollars in chemicals when spring arrives. Leaving a pool open and untreated over the winter creates a dark, stagnant breeding ground for stubborn algae and organic staining. A disciplined winterization routine preserves the water quality, meaning the pool can be reopened with minimal effort and chemical expense in May.

Skipping steps or relying on cheap, makeshift solutions like milk jugs instead of proper air pillows is a gamble that rarely pays off. High winds, heavy snow loads, and shifting ice will quickly exploit any weak points in a sloppy winter setup. Investing an afternoon of targeted prep work protects the backyard investment and guarantees a stress-free transition between seasons.

Pool Test Kit – Taylor Technologies K-2006

Closing a pool with unbalanced water chemistry is a recipe for liner degradation and metal corrosion over the long winter months. A high-precision test kit is the first line of defense, allowing pool owners to measure exactly what is happening beneath the surface before adding winterizing chemicals. Without accurate readings, chemical additions are merely guesswork, which can lead to cloudy water or scale formation.

The Taylor Technologies K-2006 service-complete kit is the industry benchmark because it utilizes precise FAS-DPD titration rather than unreliable color-matching test strips. This kit measures free and combined chlorine, pH, acid/base demand, total alkalinity, calcium hardness, and cyanuric acid with professional-grade accuracy. The liquid reagents provide immediate, highly visible color transitions that take the guesswork out of chemical balancing.

Keep in mind that these liquid reagents do have a shelf life and must be stored in a cool, dark place to maintain their accuracy for the following spring. There is a slight learning curve for those used to quick test strips, but the included waterproof instruction card makes the testing process straightforward.

• Testing Method: FAS-DPD titration for precise chlorine measurements down to 0.2 ppm
• Tests Included: Free/Combined Chlorine, pH, Alkalinity, Calcium Hardness, Cyanuric Acid
• Reagent Size: 0.75-ounce bottles

This kit is perfect for hands-on pool owners who want absolute control over their water chemistry and refuse to rely on inaccurate pool store tests. It is not ideal for those who prefer instant, low-effort readings and are willing to accept the high margin of error that comes with standard dip-strips.

Winterizing Kit – In The Swim Ultimate Winter Kit

Once the water is balanced, specialized winterizing chemicals must be introduced to prevent algae growth and scale accumulation while the pump is offline. Unlike standard summer pool chemicals, winter formulas are designed to dissolve slowly and remain active in cold, stagnant water for several months. A comprehensive kit ensures all necessary chemical bases are covered in a single, pre-measured package.

The In The Swim Ultimate Winter Kit stands out because it bundles highly concentrated, non-staining algaecides with a time-released chemical floater. It includes a powerful winterizer compound, a rust and scale preventer, and a specialized pool-closing shock that won’t bleach vinyl liners. The star of the kit is the winter slot-dispensing canister, which slowly releases sanitizing agents beneath the cover all winter long.

Buyers should ensure they select the kit size that matches or slightly exceeds their pool’s actual gallon capacity to guarantee adequate chemical coverage. Because these chemicals are highly concentrated, they must be pre-dissolved or distributed evenly across the pool water while the filtration system is still running for optimal dispersion.

• Sizing Options: Kits available for pools up to 10,000, 20,000, or 35,000 gallons
• Contents: Winter shock, Algaecide, Stain & Scale preventative, Winter chemical floater
• Compatibility: Safe for all vinyl liners and metal-framed above ground pools

This kit is an excellent choice for pool owners looking for a convenient, all-in-one chemical solution that eliminates the need to buy individual bottles. It is not necessary for those who already have a massive surplus of individual pool chemicals and prefer custom-dosing their closing regimen.

Skimmer Cover – Aquador Above Ground Skimmer Plug

Standard pool winterization often requires draining the water level below the skimmer mouth to prevent water from entering, freezing, and cracking the skimmer faceplate. However, lowering the water level too much can put structural stress on an above ground pool’s walls and vinyl liner. A skimmer plug solves this dilemma by sealing off the skimmer opening entirely, allowing the water level to remain high.

The Aquador Above Ground Skimmer Plug utilizes a snap-on plastic lid that seals directly over the skimmer opening without requiring any tool-assisted modifications. The faceplate replaces your existing skimmer faceplate permanently, while the snap-on winter cover creates a completely watertight barrier. It prevents water from entering the skimmer throat, protecting the delicate plastic housing from ice damage.

Ensure you match the Aquador model number to your specific skimmer brand (such as Hayward or Swimline) before purchasing, as bolt patterns and throat dimensions vary. The snap-on lid should be stored indoors during the summer to prevent the rubber gaskets from drying out and cracking under UV exposure.

• Material: High-density, UV-resistant plastic with rubber sealing gasket
• Compatibility: Models available for standard Hayward 1091, wide-mouth skimmers, and pool brands
• Operation: Snap-on/snap-off design, no tools required for seasonal transition

This tool is a must-have for pool owners in freezing climates who want to avoid draining their pools excessively and want to simplify the spring reopening. It is not suitable for pools with custom, non-standard skimmer shapes that do not match Aquador’s specific model dimensions.

Pool Air Pillow – Robelle Ice Equalizer Pillow

As rainwater and heavy snow accumulate on top of a winter cover, they push down on the pool water, forcing the water outward against the pool walls. An air pillow sits in the center of the pool under the cover, acting as an expansion cushion. When the pool water freezes, the ice expands inward against the compressible pillow rather than outward against the pool walls, preventing structural damage.

The Robelle Ice Equalizer Pillow is engineered to withstand extreme winter pressures without popping or leaking air. Constructed from heavy-duty, 16-gauge vinyl, this pillow features heat-sealed seams and a secure inflation valve designed to prevent slow leaks. Its robust construction ensures it remains inflated even under heavy snow loads that easily puncture cheaper, thinner alternatives.

To prevent the pillow from sliding to one side, it must be tied off using the built-in corner eyelets to anchor it directly in the center of the pool. A critical tip is to inflate the pillow to only 60 to 80 percent capacity; over-inflating leaves no room for compression, which can cause the seams to burst when ice forms.

• Material: 16-Gauge heavy-duty PVC vinyl
• Sizes Available: 4×4 feet, 4×8 feet, and 4×15 feet options
• Features: Reinforced grommets on all four corners, leak-proof air valve

This pillow is an excellent fit for pool owners in heavy snow zones who need a reliable ice compression buffer that won’t deflate mid-winter. It is less critical for mild-climate pool owners who rarely experience hard, sustained freezes that cause thick ice sheets.

Pool Cover – Blue Wave Bronze 8-Year Winter Cover

A high-quality winter cover is the primary barrier protecting your pool water from dirt, leaves, wind, and sunlight. Sunlight exposure during the offseason stimulates algae growth, while organic debris can rot and ruin the pool’s chemical balance. A secure cover keeps the water clean, dark, and ready for an easy spring opening.

The Blue Wave Bronze 8-Year Winter Cover is constructed from tough polyethylene scrim with a high-density weave that resists rips, tears, and UV degradation. The underside of the cover is black to block out all sunlight, completely stopping winter algae growth in its tracks. It features a generous 4-foot overlap, which provides plenty of extra material to accommodate the pool’s water level and the air pillow without stretching or pulling at the seams.

When sizing this cover, always purchase based on the actual pool dimensions, as the manufacturer already factors in the necessary overlap. Ensure the winch and cable assembly—which is included—is tightened securely around the pool circumference to prevent high winds from lifting the cover.

• Material: Heavy-duty polyethylene with a 7×7 scrim count
• Overlap: 4-foot overlap for secure anchoring
• Included Accessories: Vinyl-coated steel cable and heavy-duty metal winch

This cover is perfect for budget-conscious pool owners who want a durable, reliable barrier that holds up against wind and moderate snow loads. It may not be robust enough for those looking for a premium, heavy-gauge commercial cover designed to last a decade or more under extreme conditions.

Cover Pump – Little Giant APCP-1700 Cover Pump

Accumulated rain and melted snow on top of a pool cover create a massive weight load that can pull the cover off the walls and into the pool. This stagnant water also attracts mosquitoes and mixes with decomposing leaves, creating a toxic sludge that can ruin your clean pool water if it leaks through. A dedicated cover pump is essential for removing this pooling water quickly and efficiently.

The Little Giant APCP-1700 Cover Pump is a submersible utility pump designed specifically for automatic, unattended water removal. It features a built-in mechanical float switch that automatically activates the pump when water levels reach two inches and shuts it off when the cover is dry. Capable of pumping up to 1,700 gallons per hour, it clears heavy downpours rapidly before the weight can stress the pool’s top rails.

The pump features a standard garden hose connection, making it easy to route the discharge water far away from the pool’s foundation. It is vital to clean the intake screen regularly during autumn to prevent wet leaves from clogging the pump and burning out the motor.

• Flow Rate: 1,700 GPH at a 1-foot lift height
• Operation: Automatic mechanical float switch (activates at 2″, deactivates at 0.5″)
• Power Cord: 25-foot heavy-duty power cord

This pump is an indispensable tool for pool owners in wet, rainy climates who do not want to manually monitor and drain their pool covers during winter storms. It is unnecessary for pool owners in arid regions where winter precipitation is minimal and evaporation naturally keeps the cover dry.

Cover Clips – Swimline Above Ground Wall Clips

While the standard cable-and-winch system holds the winter cover in place, high winds can still get underneath the edges, flapping the cover violently and tearing the material. This wind lofting can pull the cover out of the winch assembly or damage the pool’s top rails over time. Cover clips lock the cover directly to the pool’s metal top rails, creating a wind-proof seal around the entire perimeter.

The Swimline Above Ground Wall Clips are simple, highly effective plastic clamps that grip the cover and the pool wall’s top ledge simultaneously. Made from flexible, UV-resistant ABS plastic, these clips provide strong clamping force without scratching the pool’s metal framework or tearing the vinyl cover. They prevent wind from catching the underside of the cover, ensuring it stays firmly in place even during winter gales.

For optimal wind protection, it is best to use two clips per vertical pool upright, spacing them evenly around the perimeter. Keep in mind that these clips are designed for standard above ground pools with round metal top rails and may not fit models with extra-wide resin rails.

• Material: Heavy-duty, UV-treated ABS plastic
• Quantity: Available in packs of 12, 24, or 36 to fit various pool sizes
• Compatibility: Designed for standard metal top rails on above ground pools

These clips are the perfect solution for pool owners living in open, windy areas who frequently battle cover shifting and wind lofting. They are not suitable for pools with wide, specialized resin top rails that exceed the maximum clip opening width.

Leaf Net Cover – Blue Wave Above Ground Leaf Net

Deciduous trees drop a massive volume of leaves in the autumn, which quickly turn into a wet, heavy, rotting mess on top of your pool cover. Trying to scoop these soggy leaves off a wet cover using a skimmer net is an exhausting, frustrating chore. A leaf net cover is a lightweight mesh layer that sits on top of the main winter cover to catch falling debris before it decomposes.

The Blue Wave Above Ground Leaf Net features an exceptionally tight woven mesh that catches even tiny twigs and pine needles while allowing water to pass through. Once all the autumn leaves have fallen, the pool owner simply unclasps the leaf net and lifts it off the pool, instantly removing all the debris in one swift motion. The net is constructed from durable, UV-protected polyethylene that won’t rot or degrade when exposed to standing water.

This leaf net is designed with an extra 3-foot overlap to ensure it fits comfortably over the main winter cover and the air pillow. It must be removed before the first hard freeze, as ice can lock the mesh to the primary cover, making removal impossible without tearing the materials.

• Material: Woven polyethylene mesh with reinforced binding
• Overlap: 3-foot overlap for easy installation
• Included Accessories: Heavy-duty cable and winch tensioner

This tool is an absolute game-changer for pool owners whose yards are surrounded by mature trees that drop heavy foliage every autumn. It is not necessary for pool owners with wide-open yards devoid of nearby trees or leaf-producing vegetation.

How to Drain Your Pool Lines and Equipment Safely

Water trapped inside pool plumbing, valves, and equipment during a hard freeze is guaranteed to expand and crack the rigid plastic or metal. To prevent this catastrophic damage, the filtration system, pump, and all connecting hoses must be systematically drained. Begin by disconnecting the flexible hoses that run from the pool’s skimmer and return jet to the filter system.

If the pool uses rigid PVC plumbing rather than flexible hoses, these lines must be blown out using a shop vac or specialized air blower. Once the water is completely purged from the pipes, seal the return line from the inside of the pool using a rubber expansion plug. This prevents pool water from flowing back into the plumbing lines when the winter water level fluctuates.

Do not forget to unscrew the drain plugs located at the bottom of the pool pump strainer basket and the filter tank itself. Leaving these plugs in allows residual water to pool at the bottom, which can easily crack the pump housing or the multi-port valve over the winter. Place these small plugs inside the pump basket for safe keeping so they are not misplaced during the offseason.

Storing Your Pool Pump and Filter for the Offseason

Leaving expensive mechanical equipment exposed to freezing rain, snow, and extreme temperature fluctuations drastically shortens its operational lifespan. Once the pump and filter are completely drained, they should be disconnected and moved to a sheltered environment, such as a garage or dry basement. This step protects the sensitive electrical copper windings inside the pump motor from moisture corrosion.

For sand filters, leaving the sand inside the tank is fine, but the multi-port valve should be removed and stored indoors to protect its internal rubber gaskets. Cartridge and Diatomaceous Earth (DE) filters require a thorough cleaning before storage. Spray down the filter elements with a garden hose and a specialized filter cleaner to remove accumulated oils and scale, then allow them to dry completely to prevent mold growth.

When storing the pump, inspect the rubber O-rings on the pump lid and union connections for any signs of cracking or flattening. Applying a thin coat of silicone-based pool lubricant to these seals before storing them protects the rubber from drying out. This simple maintenance task ensures an airtight seal and smooth priming when the system is hooked up again in the spring.

Final Inspection Steps Before the First Deep Freeze

The period between completing the initial winterization and the first hard freeze is crucial for making final adjustments. Wind, rain, and falling leaves can shift even the most secure covers and pillows shortly after installation. A thorough walk-around inspection ensures that all components are performing exactly as intended before freezing temperatures lock everything in place.

First, check that the air pillow remains centered in the pool and has not lost air pressure; a deflated pillow offers zero protection against ice expansion. Inspect the cover cable and wall clips to ensure they are tight and have not slipped due to high winds. If the cover has sagged excessively, use the winch to retighten the cable, keeping the cover taut but with enough slack to rest on the water’s surface.

Finally, clear any accumulated water from the cover using the cover pump one last time before the temperature drops below freezing. Once that water freezes solid, the pump cannot be used, and the heavy ice sheet will remain on the cover all winter, increasing the risk of structural stress. Double-check that all winter plugs in the return line and skimmer are seated tightly to prevent slow, hidden leaks that could drain the pool over the winter.

Taking the time to winterize an above ground pool with high-quality tools is the ultimate insurance policy for your backyard investment. By securing the cover, balancing the chemistry, and protecting the plumbing, you ensure a seamless, headache-free transition into the next swimming season. When the spring sun finally returns, you will reap the rewards of your autumn diligence with sparkling clear water and a pool structure that is ready for action.