8 Essential Closing Supplies for Your Backyard Pool

As summer warmth fades into the crisp air of autumn, the fun of backyard pool ownership transitions into the critical responsibility of winterization. Failing to prepare your pool for freezing temperatures can lead to catastrophic damage, including cracked pipes, torn liners, and ruined filtration equipment. Investing in the right closing gear now ensures a hassle-free opening next spring, saving thousands of dollars in avoidable repairs.

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Why Proper Winterization Protects Your Pool Investment

Water expands by approximately nine percent when it freezes, exerting immense outward pressure on anything containing it. In a backyard pool, this expansion can crack thick concrete walls, rupture underground PVC plumbing, and split expensive filtration tanks. Properly winterizing is not about keeping the pool clean; it is about mitigating these destructive physical forces.

Beyond structural damage, stagnant winter water becomes a breeding ground for algae and bacteria once the spring sun starts warming the cover. Unbalanced water left sitting for six months will etch plaster surfaces, stain vinyl liners, and corrode metal ladder rails. A methodical closing process preserves the structural integrity of the entire system, ensuring the pool is ready to jump into when warm weather returns.

Safety Cover – Loop-Loc Ultra-Lite Solid Safety Cover

Safety covers do more than just keep leaves out of the pool during the off-season. They act as a critical safety barrier that prevents accidental drownings of children and pets while blocking sunlight that fuels spring algae blooms. Unlike cheap tarps, a tensioned safety cover is anchored directly into the surrounding deck to withstand heavy winter snow loads and high wind.

The Loop-Loc Ultra-Lite Solid Safety Cover is the premier choice for pool owners who want the absolute protection of a solid cover without the back-breaking weight. Engineered from ultra-strong, lightweight materials, it blocks 100% of sunlight while remaining incredibly easy to handle during installation and spring removal. Its patented design ensures that water drains off safely, keeping the pool underneath pristine.

Before purchasing, consider the installation process and deck requirements. This system requires drilling brass anchors directly into concrete, wood, or pavers using a heavy-duty rotary hammer drill. * Material: Lightweight, ultra-strong composite solid fabric * Anchoring: Flush-mount brass anchors and tension springs included * Sizing: Custom and standard sizes available to match pool shape * Maintenance: Requires occasional washing and drying before spring storage

This cover is perfect for safety-conscious families with children, pets, or high wildlife activity near the pool. It is not the right choice for budget shoppers looking for a temporary, low-cost tarp, or those unwilling to drill permanent anchor holes into their pool deck.

Winter Chemical Kit – In The Swim Deluxe Closing Kit

Closing chemicals keep the water sanitized, prevent stain-causing mineral precipitation, and stop algae from taking over during the long, dark winter months. Simply dumping chlorine in before covering is not enough; you need a slow-release system designed to work in cold temperatures. Without proper winter chemicals, spring opening becomes a costly, multi-week battle against dark green water.

The In The Swim Deluxe Closing Kit compiles everything required into one convenient, pre-measured package. It includes a powerful winterizer, copper-free algaecide, metal rust inhibitors, and a slow-releasing floating sanitizer dispenser that continues working long after the cover is secured. This combination ensures your pool water remains stable and clear through freezing temperatures and early spring warming.

Using this kit requires a basic understanding of your pool’s total volume. The chemicals must be added in a specific order, and the pool filtration system should run for several hours afterward to ensure complete circulation before shutdown. * Capacity: Kits available for pools up to 10,000, 20,000, or 35,000 gallons * Components: Winterizer, Algaecide, Metal Free stain inhibitor, and Winter Floating Dispenser * Chemical Type: Concentrated, slow-release cold-water formulas * Compatibility: Safe for all pool types, including vinyl, fiberglass, and plaster

This kit is ideal for backyard pool owners looking for a foolproof, all-in-one chemical regimen that eliminates guesswork. It is not necessary for those who prefer to source individual, commercial-grade chemicals in bulk, or owners of small, temporary above-ground pools.

Pool Air Pillow – Robelle Ice Equalizer Pillow

In freezing climates, ice forms on top of the pool water and expands outward, putting immense pressure on above-ground pool walls and covers. An air pillow sits in the center of the water, absorbing this expansion force by collapsing under pressure, saving the pool walls from splitting. It also breaks up the flat plane of the cover, forcing rain and snowmelt to flow toward the edges for easier removal.

The Robelle Ice Equalizer Pillow is constructed from heavy-duty, 16-gauge vinyl designed to withstand freezing temperatures without cracking. Its secure grommeted corners allow for easy centering using ropes, ensuring the pillow stays exactly where it needs to be throughout winter storms. The rugged valves prevent air leakage under heavy snow loads, which is a common failure point for cheaper alternatives.

Proper inflation is the most critical factor when using this tool. Never inflate the pillow to 100% capacity; leaving it at roughly 60% to 75% inflation allows the pillow to compress without popping when the ice squeezes it. * Material: Heavy-duty, 16-gauge cold-resistant vinyl * Features: Reinforced grommeted corners for secure tie-downs * Sizes: Available in 4×4, 4×8, and 4×15 foot options * Application: Primarily for above-ground pools, but highly useful for in-ground pools with solid covers

This is an essential safety item for above-ground pool owners in regions that experience hard, prolonged freezes. It is not needed for pool owners in southern climates that do not experience freezing temperatures.

Pool Cover Pump – Little Giant APCP-1700 Cover Pump

Rainwater and melting snow quickly accumulate on solid pool covers, creating a heavy pool of water that can damage the cover, pull anchors loose, or drown small animals. A reliable cover pump automatically removes this standing water before it becomes a hazard or a breeding ground for mosquitoes. Leaving water to sit on a cover shortens its lifespan and makes spring removal incredibly messy.

The Little Giant APCP-1700 Cover Pump is the industry standard for automatic water removal. It features an integrated mechanical float switch that automatically turns the pump on when water reaches two inches and shuts it off once the cover is dry, preventing dry-running damage. The wide, stable base prevents the pump from tipping over on uneven cover surfaces.

The pump requires a continuous, outdoor-rated GFCI power source and a clear path for the discharge hose. The intake screen must be kept clear of wet leaves and debris to prevent clogging and motor burnout. * Flow Rate: Moves up to 1,745 gallons per hour * Connection: Standard 3/4-inch garden hose thread * Power: 1/3 horsepower motor with a 25-foot power cord * Activation: Automatic mechanical float switch (no manual monitoring needed)

This pump is a must-have for anyone using a solid winter cover or tarp that collects standing water. It is not necessary for those with mesh safety covers, as rainwater naturally drains straight through into the pool.

Skimmer Plug – Gizzmo Ultra Expansion Skimmer Bottle

If water gets into the skimmer throat and freezes, the expanding ice will crack the delicate plastic skimmer housing, requiring a costly excavation and replacement. A specialized skimmer plug seals off the plumbing line while absorbing any ice expansion that occurs inside the skimmer itself. It acts as a cheap insurance policy against one of the most expensive winter freeze repairs a pool owner can face.

The Gizzmo Ultra Expansion Skimmer Bottle serves a dual purpose: it threads directly into the bottom of the skimmer to seal the plumbing line, and its hollow, collapsible plastic body absorbs the expansion of ice inside the skimmer well. The Ultra model features a 1.5-inch and 2-inch double thread, making it universally compatible with most in-ground skimmers without the need for adapters.

Always use Teflon tape on the threads to ensure an airtight and watertight seal before screwing the Gizzmo into place. Ensure the skimmer well is completely free of debris and dry before installation. * Threads: Dual 1.5-inch and 2-inch male threads * Material: High-density, collapsible polyethylene * Design: Built-in blow-out tube for purging plumbing lines * Length: 16 inches for deep-well skimmer protection

This is a crucial protective tool for in-ground pool owners in freezing climates who want to avoid expensive concrete deck excavation repairs. It is not designed for above-ground pool skimmers that do not feature threaded bottom plumbing connections.

Winter Expansion Plug – Anderson Winterizing Plug

Once the plumbing lines are blown out and cleared of water, they must be sealed airtight to prevent water from creeping back in from the pool. Winter expansion plugs seal returns, cleaner lines, and main drains, keeping the plumbing dry and safe from freezing forces. Without these plugs, water will quickly seep back into the pipes, freeze, and cause underground ruptures.

Anderson Winterizing Plugs are engineered with premium industrial-grade rubber and stainless steel wing nuts that resist corrosion in wet, chemical-heavy environments. The ribbed rubber body expands evenly when the wing nut is tightened, creating a reliable, high-pressure seal that will not slip under pressure. Their heavy-duty construction means they can be reused season after season without degrading.

Measuring your return fittings before purchase is essential, as these plugs come in highly specific sizes. Do not over-tighten the wing nuts, as excessive force can crack the plastic return fittings inside the pool wall. * Material: Chemical-resistant rubber with stainless steel hardware * Sizing: Available in sizes ranging from #0 (micro) to #14 (large pipe) * Application: Suitable for return lines, cleaner lines, and skimmers * Durability: Heavy-duty construction designed for multi-season reuse

These plugs are necessary for any pool owner winterizing an in-ground or above-ground pool with plumbing lines below the winter water level. They are not needed for temporary pools that are completely disassembled and stored indoors for the winter.

Pool Leaf Net – Blue Wave Rectangular Leaf Net Cover

Deciduous trees shed millions of leaves in autumn, which rot on top of your pool cover, creating a heavy, foul-smelling sludge that is incredibly difficult to clean in the spring. A leaf net sits on top of your main cover, catching these leaves so you can easily peel them off in one quick motion once the trees are bare. It turns hours of messy spring scooping into a five-minute job.

The Blue Wave Rectangular Leaf Net Cover is made from durable woven polyethylene with a tight mesh that catches even small twigs and pine needles. It features a heavy-duty perimeter cable and winch system that secures the net tightly over the main cover, preventing winds from whipping it loose. The lightweight material makes it easy to lift, even when loaded with wet leaves.

This net must be installed before leaves begin to fall and removed once the trees are completely bare in late autumn. It requires two people to peel off smoothly without dumping the collected leaves back onto the main cover. * Material: Heavy-duty, UV-protected woven polyethylene mesh * Hardware: Vinyl-coated steel cable and metal winch included * Overlap: 4-foot overlap ensures complete coverage of the pool surface * Weight: Exceptionally lightweight for easy handling and removal

This is an invaluable time-saver for pool owners with heavy tree canopy coverage near their pool. It is not necessary for pools located in open, treeless yards where wind-blown debris is minimal.

Pool Line Blower – Cyclone Pro Heavy Duty Line Blower

Getting every drop of water out of underground plumbing lines is the most critical step in preventing catastrophic freeze cracks. A specialized, high-volume line blower forces water out of the lines with high volume and low pressure, ensuring no water remains to freeze. Standard shop vacs often lack the power to push water out of deep main drains, leaving systems vulnerable.

The Cyclone Pro Heavy Duty Line Blower is the gold standard for pool professionals and DIYers alike, offering a powerful 3.0 horsepower motor that bypasses the limitations of consumer vacuums. It generates enough air volume to clear main drains under ten feet of water, as well as multiple return lines simultaneously. The durable plastic housing protects the motor from damp outdoor environments.

Operating this blower requires a heavy-duty, 12-gauge extension cord to handle the high electrical draw safely. It connects directly to the pool skimmer or pump basket using specialized quick-connect hoses. * Motor: Powerful 3.0 HP bypass motor * Performance: Up to 140 CFM of high-volume air flow * Hose: 1.5-inch flexible hose with quick-connect fittings * Housing: Lightweight, corrosion-resistant plastic shell

This is a premium investment for dedicated DIY pool owners who want to avoid paying hundreds of dollars to pool service companies every year. It is not suited for casual pool owners who prefer to delegate the technical aspects of pool winterization to professional crews.

How to Clear and Blow Out Your Pool Plumbing Lines

Clearing your plumbing lines requires a systematic, step-by-step approach to ensure no pockets of water remain. Start by lowering the pool water level below the skimmer mouth and returns, then hook up your line blower to the pump basket or skimmer. Turn on the blower and open the valve for the shallowest return line first, allowing the air to force the water out until you see a steady mist, then a blast of pure air.

Once a line is cleared, slide your expansion plug into the return fitting while the air is still blowing to prevent water from back-flowing into the pipe. Repeat this process for each return, moving from the closest to the furthest from the equipment pad. Finally, tackle the deep-end main drain by blowing air until a massive geyser of bubbles erupts in the pool, then quickly close the slide valve at the equipment pad to lock the air lock in place.

Balancing Your Water Chemistry Before the Big Freeze

Adjusting your water chemistry before closing is the difference between opening a clean, clear pool and uncovering a toxic swamp. Calcium hardness, pH, and total alkalinity must be perfectly balanced to prevent the water from becoming corrosive or scale-forming over the winter. When water temperatures drop, unbalanced water becomes highly aggressive, attacking plaster, tile grout, and metal components.

Aim for a pH between 7.2 and 7.6, total alkalinity between 80 and 120 ppm, and calcium hardness between 200 and 400 ppm. Run your filtration system for at least 24 hours after adding balancing chemicals to ensure thorough mixing before adding your closing shock and algaecide. Never add shock and algaecide at the same time, as high chlorine levels will destroy the active ingredients in the algaecide, rendering it useless.

Storing Your Filtration Equipment Safe From Freezing

Leaving water inside your pump, filter, or heater over the winter is a guaranteed recipe for expensive equipment failure. Sand, cartridge, and DE filters all have drain plugs at their lowest points that must be removed to allow all internal water to escape. Keep these plugs in the pump basket or store them indoors so they do not get lost before spring startup.

Unbolt your pump motor, disconnect the plumbing unions, and store the pump assembly in a dry, temperature-controlled environment like a basement or garage. If you have a saltwater pool, remove the salt chlorine generator cell, clean it with a mild acid solution if necessary, and store it indoors to protect the delicate electronics from extreme cold. For gas heaters or heat pumps, blow out the internal heat exchanger tubes with air to prevent internal cracking.

Taking the time to properly winterize your backyard pool with high-quality gear is the ultimate insurance policy for your outdoor investment. By securing reliable safety covers, clearing the lines completely, and balancing the chemistry, you protect your system from costly frost damage. When warm weather returns, you will reap the rewards of a smooth, stress-free opening day on the water.