8 Essential Winterizing Supplies for Your Inground Pool

As autumn leaves start to drop, the cooling breeze signals that it is time to transition your backyard oasis from a summer playground to a secure winter fortress. Proper winterization is not just about keeping the pool clean; it is a critical protective measure against costly structural damage caused by freezing temperatures. Equipping yourself with the right tools ensures that your inground pool survives the harsh winter months unscathed and opens beautifully in the spring.

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Why Winterizing Your Inground Pool Matters

Leaving an inground pool vulnerable to freezing temperatures can result in catastrophic structural and mechanical failures. When water freezes, it expands by approximately nine percent, exerting immense outward pressure. This expansion can easily crack heavy concrete skimmers, split underground PVC pipes, and pop tiles off the pool wall.

A proper winterization routine acts as an insurance policy for your major backyard investment. By proactively clearing plumbing lines, balancing water chemistry, and deploying defensive covers and plugs, pool owners avoid thousands of dollars in springtime repairs. Preparing the pool correctly also prevents a toxic, swamp-like algae bloom from taking over, making the spring opening process quick and effortless.

Pool Safety Cover – Loop-Loc Safety Pool Cover

A pool safety cover is the first line of defense against winter debris, harsh weather, and accidental falls. Standard tarp covers held down by water bags can easily collapse under heavy snow loads, dumping dirty water and leaves directly into your clean pool. A high-quality safety cover stretches taut across the pool deck, functioning like a tight trampoline that keeps unwanted elements out while securing the area.

The Loop-Loc Safety Pool Cover stands out as the industry standard because of its legendary strength and durability. Constructed from ultra-strong, lightweight polypropylene mesh, this cover allows rain and melting snow to drain through while blocking dry debris and heavy leaves. The patented brass anchor system secures directly into your concrete deck, ensuring the cover stays locked in place even during high-wind winter storms.

• Material: High-strength polypropylene mesh
• Weight Capacity: Designed to support thousands of pounds of static weight
• Hardware: Corrosion-resistant brass anchors and stainless steel springs
• Warranty: 15-year pro-rated manufacturer warranty

Before purchasing, accurate measurements of your pool’s coping and deck layout are absolutely critical. Custom-shaped pools require precise step and corner measurements to ensure a drum-tight fit. This premium cover is the perfect choice for homeowners prioritizing safety and longevity, though it is not ideal for budget-conscious owners looking for a temporary, one-season solution.

Winter Chemical Kit – In The Swim Deluxe Pool Kit

Closing your pool with unbalanced water guarantees an uphill battle against algae, staining, and scale deposits when spring arrives. Stagnant water sitting under a dark cover for six months creates a prime breeding ground for microscopic organisms. A dedicated winter chemical kit slow-releases sanitizing agents and mineral protectors to keep the water clear and pristine during dormancy.

The In The Swim Deluxe Pool Kit provides a comprehensive, pre-measured chemical regimen designed specifically for winter conditions. This kit includes a non-chlorine winter shock to oxidize contaminants, a powerful winter algaecide to prevent green growth, and a metal-free stain preventer. It also features a time-released chemical dispenser that floats beneath the cover, continually treating the water as temperatures fluctuate.

• Capacity: Formulated for pools up to 35,000 gallons
• Kit Components: Winterizer chemical dispenser, non-chlorine shock, winter algaecide, metal-free stain preventer
• Compatibility: Safe for plaster, fiberglass, and vinyl-liner pools
• Active Duration: Designed to protect water for up to six months of winter closure

To get the most out of this kit, pool owners must distribute the chemicals evenly by running the pool pump for at least four to six hours before lowering the water level. This ensures complete circulation of the protective agents into every corner of the pool. This kit is ideal for owners who want an all-in-one chemical solution, but it may be unnecessary for those who prefer to source and measure individual winterizing chemicals independently.

Pool Air Pillow – Robelle Ice Equalizer Pillow

For pools utilizing solid covers or solid leaf nets, rainwater and melting snow can quickly accumulate in the center, creating a massive, heavy puddle. This concentrated weight pulls on the cover straps, stressing the deck anchors and risking a total cover collapse. An air pillow placed beneath the cover breaks the surface tension, shifting the weight of the water toward the pool perimeter where a cover pump can easily reach it.

The Robelle Ice Equalizer Pillow is manufactured from heavy-duty, 16-gauge vinyl designed to withstand extreme cold without becoming brittle. It features an air-tight valve that prevents pressure loss under heavy snow loads, and reinforced grommets on the corners for easy positioning. By remaining inflated all winter, it creates a gentle dome effect under solid pool covers.

• Material: Heavy-duty 16-gauge vinyl
• Dimensions: 4 x 4 feet (larger options available)
• Grommets: Heavy-duty corner eyelets for centering ropes
• Inflation Valve: Dual-seal leak-resistant valve

A common mistake is inflating the air pillow to 100 percent capacity; doing so leaves no room for compression, causing the pillow to pop when ice or snow presses down. It should only be inflated to 60 to 80 percent capacity to allow for natural compression. This accessory is essential for owners using solid winter covers, but it is not necessary for those using high-tension, free-draining mesh safety covers.

Expansion Plug – Hayward SP1022B Rubber Plug

Once you blow the water out of your pool’s return lines, keeping water from seeping back in is critical. If water re-enters the plumbing lines and freezes, the expanding ice will crack the underground PVC pipes, resulting in devastating leaks. Expansion plugs are inserted into the return fittings and tightened to create an airtight, watertight seal.

The Hayward SP1022B Rubber Plug is an industrial-grade expansion plug built for the demanding environment of winter pool storage. It features a durable, tapered rubber body that compresses outward when the wing nut is tightened, sealing the pipe completely. The inclusion of high-quality stainless steel and brass hardware ensures that the moving parts will not rust or seize after months of contact with water.

• Diameter: 1.5 inches (standard return line size)
• Hardware: Corrosion-resistant brass bolt and stainless steel wing nut
• Body Material: High-grade, chemical-resistant neoprene rubber
• Quantity: Sold individually or in multi-packs

Ensure you match the plug size to your specific return line fittings, as some older pools may utilize 2-inch or custom-sized plumbing. Tighten the wing nut firmly by hand to ensure a secure fit, but avoid using heavy tools that could strip the threads. These plugs are a mandatory requirement for anyone winterizing an inground pool in a climate that experiences hard, sustained freezes.

Skimmer Guard – Gizzmo Ultra Freeze Protection

The pool skimmer is one of the most vulnerable components of an inground pool because it sits right at the freeze line. As surface ice expands, it pushes against the plastic skimmer walls, which can easily crack the housing and require expensive excavation to repair. A skimmer guard absorbs this destructive expansion pressure, collapsing inward to protect the surrounding plastic.

The Gizzmo Ultra Freeze Protection is a hollow, heavy-duty plastic tube designed to screw directly into the female threads at the bottom of your skimmer. It acts as a sacrificial expansion chamber; when ice forms inside the skimmer, it compresses the flexible Gizzmo rather than cracking the skimmer walls. The Ultra model features a built-in blow-out channel, allowing you to clear the plumbing line without removing the guard.

• Thread Size: 1.5-inch and 2-inch dual tapered threads
• Length: 16 inches for deep skimmer wells
• Material: Heavy-gauge, impact-resistant molded plastic
• Feature: Built-in blow-out tube with a rubber cap

Always wrap the Gizzmo’s threads with several layers of Teflon tape before screwing it into the skimmer to ensure an airtight seal and easy removal in the spring. This product is designed specifically for standard inground skimmers with threaded bottom ports. It is not suitable for non-standard skimmers or pools in regions where the surface water never reaches freezing temperatures.

Pool Antifreeze – Splash Non-Toxic Antifreeze

Even after using a powerful blower, small pockets of water can remain trapped in low spots of underground plumbing lines. If these small pockets of water freeze, they can still cause localized pipe ruptures. Adding specialized pool antifreeze to the plumbing lines provides an essential safety margin against residual moisture damage.

Splash Non-Toxic Antifreeze is a propylene-glycol-based formula designed to protect pool plumbing down to extreme sub-zero temperatures. Unlike toxic automotive antifreeze, which contains ethylene glycol, this formula is non-toxic, eco-friendly, and safe for local wildlife and pool finishes. It will not damage your pool’s vinyl liner or plaster walls when the lines are flushed out in the spring.

• Base Compound: Non-toxic propylene glycol
• Protection Level: Burst protection down to -50°F (-45°C)
• Volume: 1-gallon bottles
• Safety: Safe for lawns, pets, and local sewer systems

This product must be poured directly into the cleared plumbing lines via the skimmer or return lines; never pour pool antifreeze directly into the main pool water. It is formulated specifically for plumbing lines and should not be diluted with water inside the pipes. This is a must-have product for pool owners in northern climates, but it can be skipped by pool owners in mild southern climates that do not experience hard freezes.

Pool Cover Pump – Little Giant APCP-1700 Pump

Solid pool covers act as giant basins that catch every drop of winter precipitation. Left unchecked, thousands of pounds of standing water will build up, creating a drowning hazard and risking damage to your cover and pool walls. An automatic cover pump monitors this water accumulation and pumps it away before it can freeze into a solid sheet of ice.

The Little Giant APCP-1700 Pump is a submersible utility pump designed specifically for the harsh conditions of winter pool covers. It features an integrated mechanical float switch that automatically activates the pump when water reaches two inches, and shuts it off when the level drops to half an inch. With a flow rate of up to 1,745 gallons per hour, it clears heavy accumulation rapidly.

• Flow Rate: 1,745 GPH at a 0-foot lift height
• Switch Type: Automatic mechanical float switch
• Power Cord: 25-foot heavy-duty power cord
• Discharge Connection: Standard 3/4-inch garden hose adapter

Keep the pump intake screen clear of leaves and twigs to prevent the motor from running dry or clogging. It is crucial to plug this pump into a certified GFCI outlet to ensure electrical safety around standing water. This pump is an indispensable tool for solid cover users, but it is not necessary for those using self-draining mesh safety covers.

Pool Leaf Net – Blue Wave Rectangular Leaf Net

If your yard is surrounded by deciduous trees, autumn can cover your pool area in a thick blanket of heavy, wet leaves. These leaves rot quickly, staining pool surfaces and creating a heavy muck that is incredibly difficult to clean off your winter cover. A leaf net sits on top of your primary winter cover, catching leaves before they can decompose and weigh down your main defense system.

The Blue Wave Rectangular Leaf Net is made from durable, woven polyethylene mesh that stands up to sharp twigs and heavy wind. It features a generous four-foot overlap, ensuring a secure fit over the edges of your pool deck. Once the trees have finished shedding their leaves, you simply lift the net off the pool, discarding all the collected leaves in one swift motion.

• Material: Heavy-duty woven polyethylene mesh
• Overlap: 4-foot overlap for secure anchoring
• Fasteners: Heavy-duty brass grommets and a vinyl-coated steel cable with winch
• Weave: Tight mesh to catch small debris and pine needles

This net must be removed before the first heavy snowfall or hard freeze of the season. If left on during a freeze, the leaves and net can become trapped in solid ice, making removal impossible until spring. This net is highly recommended for wooded properties, but it is a superfluous expense if your pool deck is clear of overhanging trees.

How to Clear and Blow Out Your Plumbing Lines

Clearing water from your pool’s plumbing lines is the most critical step in prevent freeze damage. To perform this task effectively, pool owners use a high-volume air blower or a heavy-duty shop vacuum connected to the plumbing lines at the equipment pad. By forcing air through the lines, you push all standing water out through the return jets and skimmer ports.

Start by lowering the pool water level to roughly four to six inches below the skimmer mouth. Connect your blower to the return line plumbing at the filtration pad, turn it on, and watch for water to begin bubbling out of the return jets inside the pool. Once the line is blowing pure air with no water vapor, slide an expansion plug into the jet and tighten it securely to create an airtight seal.

Repeat this process for every line, including the main drain at the deep end of the pool. When blowing out the main drain, look for a massive column of air bubbles rising to the surface, then quickly close the valve at the equipment pad to create an “air lock” that prevents water from traveling back up the pipe. Adding a splash of non-toxic antifreeze into the lines before plugging them adds an extra layer of protection.

Balancing Pool Water Before the Final Freeze

Closing your pool with unbalanced water can cause permanent etching on plaster surfaces, ruin vinyl liners, and promote aggressive algae growth. When water temperatures drop below 60°F, chlorine stabilizes, but overall water chemistry remains dynamic. Ensuring your levels are balanced before the final freeze prevents cosmetic and structural degradation of your pool’s interior.

Begin by testing the water with a high-quality test kit at least one week before you plan to close the pool. The target chemical levels for winterization are slightly different than standard summer parameters: * pH: 7.2 to 7.6 * Total Alkalinity: 80 to 120 ppm * Calcium Hardness: 200 to 400 ppm * Chlorine: 1 to 3 ppm

Adjust the total alkalinity first, as this stabilizes the pH and prevents wild fluctuations during the winter months. Once the alkalinity and pH are locked in, add your calcium hardness increaser if necessary, followed by your winterizing shock and algaecide. Run your filtration system for 24 hours to ensure these chemicals are thoroughly distributed throughout the entire body of water.

Proper Storage for Your Filter and Pump Gear

Your pool’s mechanical equipment pad contains expensive, precision components that are highly susceptible to damage from freezing water. Leaving water inside pumps, filters, and heaters will result in cracked housings and ruined internal components. Preparing these components for winter storage requires systematic draining and sheltered storage.

Begin by shutting off all electrical power to the pool pad at the main breaker panel. Remove all the drain plugs from your pump strainer basket housing, your sand or D.E. filter tank, and your pool heater. Store these small drain plugs inside the pump basket so they do not get lost over the winter months, and leave the drain valves open to allow any remaining condensation to escape.

If you have a cartridge filter, remove the cartridges, spray them down with a filter cleaner, let them dry completely, and store them indoors. For multi-port valves, set the handle to the “Winter” or “Closed” position to relieve pressure on the internal rubber gaskets. Unplug pressure gauges and chemical feeders, and store them in a climate-controlled area to prevent delicate plastic components and O-rings from drying out and cracking.

Conclusion

Taking the time to systematically winterize your inground pool with high-quality, task-specific gear is the ultimate way to protect your backyard investment. By deploying robust safety covers, reliable expansion plugs, and specialized winter chemicals, you insulate your pool from the destructive power of freezing winter weather. When spring arrives, you will reap the rewards of your diligence, opening a clean, clear, and undamaged pool ready for another season of warm-weather fun.