Gizzmo vs Rubber Plug: Best Way to Winterize a Skimmer?

First, Understand What Threatens Your Skimmer in Winter

Choosing a method means understanding the risk. Water expands as it freezes. If that water is confined inside your skimmer body or its attached pipe, the expanding ice needs an escape route. When it finds none, the pressure can fracture the rigid plastic skimmer. This is the core problem every winterization technique aims to solve.

Both a rubber plug and a Gizzmo accomplish one shared goal: they seal the skimmer's suction line to prevent water from re-entering the system. The key difference is that a Gizzmo provides an additional function. It creates a sealed, compressible air pocket within the skimmer throat. As surrounding water freezes and expands, this cushion compresses, absorbing pressure like a relief valve before it can damage the housing. This purpose-engineered protection is why the Gizzmo is often considered the dedicated solution for skimmer freeze damage.

Why a Simple Rubber Plug Sometimes Succeeds

The reality is, a basic plug can be enough under specific conditions:

• The pool water is lowered below the skimmer. If no water remains in the skimmer basket area, there's nothing present to freeze and expand. Many pool owners who rely on a plug also significantly lower the water level—often enough to empty the skimmer throat—as their main defense. Always verify the precise level recommended by your skimmer's manufacturer.
• Antifreeze is added to the skimmer. Adding antifreeze is usually not necessary if the line is properly blown out. It is an optional backup for a line that couldn't be fully cleared. If used, only pool-safe propylene glycol antifreeze should be poured into the plumbing line itself.
• Local winter climate. In areas with mild winters featuring only brief, light frosts, the danger of cracking is reduced, and simpler methods may suffice. In regions with prolonged, deep freezes, the need for robust protection is greater.

Your neighbor is likely combining his plug with one or more of these steps—or perhaps his local winters are lenient, or he's been fortunate. This isn't a criticism; it's simply circumstance.

A common and effective DIY alternative to a Gizzmo is using a plastic bottle (like a half-filled milk jug with the cap on). It sits in the skimmer body, and ice squeezes the compressible jug instead of the skimmer walls. It's cheap and does the same cushioning job as a Gizzmo's air pocket. However, it does not seal the pipe, so you would still need a rubber plug in the skimmer's suction port.

The Specific Advantages a Gizzmo Provides

The Gizzmo's benefit is most apparent in colder regions or when skimmer lines aren't perfectly dry. Its compressible design makes it a sacrificial buffer. If ice pressure builds, it will crush the Gizzmo before transferring that force to the skimmer housing—this is the intended failure mode. Swapping a damaged Gizzmo in spring is simple and cheap; repairing or replacing a cracked skimmer is a major project.

Enhanced models are also available. Some accommodate both 1.5-inch and 2-inch pipe openings, common sizes for inground skimmers—though you should verify your skimmer's pipe diameter before buying. Other versions include a built-in blow-out valve, allowing you to clear plumbing lines without taking out the device. For those new to winterizing, such features can help prevent errors.

Is the Skimmer Cover Plate Still Necessary?

Yes, absolutely. The Gizzmo does not eliminate the need for it. The cover plate (or winter skimmer cover/closure plate) has a separate role: it seals the top of the skimmer opening at deck level to block debris, rain, and melting snow from filling the skimmer basket over winter. Without it, you'll face a skimmer full of decayed leaves come spring, and debris could still enter the pipe even with a Gizzmo in place below.

Consider it this way: the Gizzmo guards the plumbing from below; the cover plate guards the skimmer cavity from above. They are complementary, not substitutable.

Recommended Steps for a First-Time DIY Pool Closing

1. Blow out the skimmer lines using a shop vac or air compressor before installing any device. Eliminating as much water as possible is your primary defense against freezing, no matter which plug you choose.
2. (Optional / Usually Not Needed) Pour a small quantity of pool-safe propylene glycol antifreeze into the skimmer suction line for extra security. This must go into the line before you seal the port with your plug or Gizzmo.
3. Install the Gizzmo or rubber plug by threading it into the skimmer throat until snug. Avoid overtightening; you want a secure seal, not stripped threads.
4. Place the skimmer cover plate on top to shield the skimmer throughout the off-season.

For a comprehensive, step-by-step guide to the entire closing procedure—not just the skimmer—our pool winterization and closing guide details everything from pre-closing chemical balance to equipment protection.

Final Verdict

Your neighbor's approach can be effective, but it hinges on perfect execution and favorable weather. A Gizzmo offers more forgiveness; it's engineered for this specific task and supplies a mechanical safety net a plain rubber plug lacks. For a first solo closing, the added peace of mind justifies its use. Combine it with a skimmer cover plate, ensure the lines are blown out first, and your pool will be well-protected until spring.

The Classic Closing Kit

★★★★★★★★★★ 4.7 (9,649)

In The Swim chlorine-free winter kit — closing chemicals for pools up to 15,000 gallons, with stain-away.

See the In The Swim kit →onamazon

Sponsored