What's the difference between a box skimmer and an in-pond skimmer?

A box skimmer is plumbed into the pond wall with a weir door and usually gets installed during construction. An in-pond skimmer sits directly in the water and works as a retrofit without touching the liner. Both pull surface debris before it sinks, but installation and disruption to an existing pond are very different.

How do I size a skimmer for my pond?

Match the skimmer to your pond's water volume and the pump's flow rate. A skimmer rated below your pond's needs runs constantly without keeping up, and one that's oversized can put more suction on the weir than the door is built to handle. If you're not certain what your pond needs, call us with your pond's dimensions and we'll help you figure it out.

How often should I clean or replace the skimmer mat or basket?

Check the debris basket every few days during heavy leaf drop and weekly the rest of the year. Filter mats should be rinsed periodically and replaced once they lose their shape or stop trapping fine debris, usually once a season depending on your pond's debris load.

Will a pond skimmer keep working through a Pacific Northwest winter?

Most skimmers here keep running through a typical Puget Sound winter, since hard, sustained freezes are less common than further inland. Some pond owners still pull the pump during an extended cold snap as a precaution. If you're unsure what's right for your setup, ask us before the first freeze.

Can I retrofit a skimmer into an existing pond?

An in-pond submersible skimmer is the easier retrofit option, since it doesn't require cutting the liner. Installing a box skimmer into an already-built pond is possible but usually means reworking the edge, which is a bigger project.

What's the difference between a skimmer and a skimmer net?

A skimmer is a mechanical device that continuously pulls surface water and debris toward an intake. A skimmer net is a hand tool you use to manually scoop debris off the surface. They work well together, but a net doesn't replace the continuous action of a skimmer.

Skimmers

Q: Can I add UV clarification to my skimmer?

Yes, on select models. Aqua Ultraviolet Retrofit UV Clarifier for Savio Skimmerfilter (15 Watt, 25 Watt & 57 Watt) and Savio UVinex 'High Output' System (For Savio Standard & Compact SkimmerFilters) both retrofit into Savio skimmer housings so you don't need a separate inline UV unit.

A pond skimmer pulls floating debris off the surface before leaves, pollen, and grass clippings sink and start breaking down in your water. This collection covers the skimmers and skimmerfilters we carry for Pacific Northwest ponds and water gardens, from compact in-pond units for a small backyard feature to high-flow box skimmers built for koi ponds with heavy fall leaf drop.

You'll find two main styles here. Box skimmers, sometimes called skimmerfilters, sit against or inside the pond wall, house the pump or connect to one, and use a weir door that adjusts to water level so the surface pull stays constant. In-pond submersible skimmers float or sit directly in the water without wall-mounted plumbing, which makes them a simpler retrofit for an existing pond. We also stock the skimmer pumps, UV add-ons, replacement weir assemblies, filter mats, and manual skimmer nets that keep these systems running through leaf season and beyond.

What's Included in This Category

This category covers the skimming and surface-filtration equipment we stock for backyard water features, water gardens, and koi ponds: box skimmers (skimmerfilters), in-pond submersible skimmers, the pumps built to run inside a skimmer housing, UV clarifier add-ons, and the service parts, weir assemblies, and filter mats that keep a skimmer working season after season. We also carry hand-held skimmer nets separately, since they solve a different problem than a mechanical skimmer does, covered further down.

Box Skimmers vs. In-Pond Skimmers

Most of what's in this category falls into one of two builds, and picking the wrong one for your situation is the most common mistake we see on new pond projects.

Box Skimmers (Skimmerfilters)

A box skimmer, often labeled a skimmerfilter, sits against the pond edge with a weir door built into the liner or set into a vault, and a basket behind the door traps leaves and debris before it reaches the pump or filter media inside. Aquascape Signature Series 200 Pond Skimmer, Aquascape Signature Series 400 Pond Skimmer, and Aquascape Signature Series 1000 Pond Skimmer scale by pond size, while Savio Standard Skimmerfilter SS0000 & Weir Assembly and Savio Compact Skimmerfilter W/ 8.5" Weir Assembly are common on koi ponds already running Savio filtration. The Atlantic - Skimmers - Models - PS3000, PS3900, PS4600, PS7000 & PS15000 line covers a wide flow range in one family, EasyPro Pro-Series Pond Skimmers and EasyPro Axiom Pond Skimmers suit larger installations, and Oase ProfiSkim 100 Low Profile In-Pond Skimmer is worth a look if deck height or liner depth is tight.

Box skimmers get installed during construction in most cases, since they need to be plumbed into the liner. Retrofitting one into a finished pond is possible but involves cutting the liner and reworking the edge, a bigger job than most DIY owners want to take on.

In-Pond Submersible Skimmers

An in-pond or submersible skimmer sits directly in the water rather than being built into the wall. PondMAX Submersible In-Pond Skimmer PS450 and Oase AquaSkim 40 Surface Skimmer both work this way, pulling debris through an intake without any liner cutting, and EasyPro Pond Skimmers for External Pumps takes a similar approach but pairs with an external pump rather than housing its own. This style is the easier retrofit: if you already have a pond running and don't want to drain it or cut the liner, an in-pond skimmer gets you most of the benefit without the construction.

Matching a Skimmer Pump to Your Skimmer

Many box skimmers are sold as the housing only, with the pump chosen separately to match the pond's flow needs. PondMaster High-Head Skimmer Pumps and PondMAX EVO II Skimmer & Water Feature Pumps both sit inside a skimmer vault and push water up to a waterfall or filter. An undersized pump won't keep up with debris, and an oversized one can strain the weir door or overwhelm a small basket. If you're not sure what your skimmer is rated for, call us before buying a pump separately.

Choosing the Right Skimmer for Your Pond

Pond Size and Flow Rate

Bigger ponds move more water and collect more debris, so they need a skimmer rated for higher flow. A skimmer that's too small runs constantly and still leaves debris behind, since it can't process the surface fast enough.

Debris Load and Placement

Position matters as much as size. Skimmers work best placed opposite the prevailing wind, so debris drifts toward the intake instead of away from it. In the Puget Sound region, that debris load leans heavily toward fir needles, bigleaf maple leaves, and alder catkins, peaking from late September through November, with cottonwood fluff adding a second wave in early summer.

New Build vs. Retrofit

If you're building a new pond, a box skimmer is worth planning into the design from day one. If you're working with an existing pond and don't want to touch the liner, an in-pond submersible skimmer is the more practical route.

Keeping a Skimmer Running: Parts and Add-Ons

A skimmer is only as good as its maintenance. Savio Standard SkimmerFilter Replacement Parts and Savio Compact SkimmerFilter Replacement Parts cover the mats, baskets, and hardware that wear out first on Savio units, and EasyPro Skimmer Extension Tubes let you adjust plumbing runs without buying a whole new unit. If you want UV clarification built into your skimmer setup instead of a separate inline unit, Aqua Ultraviolet Retrofit UV Clarifier for Savio Skimmerfilter (15 Watt, 25 Watt & 57 Watt) and Savio UVinex 'High Output' System (For Savio Standard & Compact SkimmerFilters) both retrofit into existing Savio housings.

Manual Skimmer Nets Are a Different Tool

A skimmer net is not the same product as a skimmer. Aquascape Professional Grade Pond Skimmer Net, Aquascape Heavy Duty Pond Skimmer Net with Extendable Handle, and Aquascape Collapsible Pond Skimmer Net are hand tools for scooping leaves and debris off the surface. They're a good companion to a mechanical skimmer, not a replacement for one, since they only clean what you can reach in the moment rather than running continuously.

Seasonal Skimmer Care in the Pacific Northwest

Fall is the heaviest season for any skimmer here. Deciduous trees drop through October and into November, and a skimmer basket that goes unchecked for two weeks during peak drop backs up fast. Plan on emptying it every few days during that stretch.

Winters in the Puget Sound area rarely bring the hard, sustained freeze that shuts equipment down further inland, but a skimmer pump left running through a cold snap can still ice up at the intake. Many pond owners here keep the skimmer running through a mild winter and only pull the pump if a hard freeze is forecast. Spring cleanup is the other checkpoint: rinse or replace the filter mat, check the weir door for stiffness, and clear the basket before the pond's growth cycle pushes the debris load back up.