When fall arrives, pond owners need to start thinking about preparing their small backyard pond for the winter temperatures. This isn’t a large natural water runoff pond that can fend for itself. We’re talking about a decorative pond with a filtration system, a pump, aquatic plants, and maybe some hardy fish. Winterizing a pond properly will help protect your equipment, maintain oxygen levels to safeguard aquatic life, and ensure everything is ready to go when warm weather returns.

Why is fall shutdown important?

Getting a pond ready for winter is crucial, especially when in a colder climate. Freezing temperatures can cause damage to equipment like pumps, filter materials, and pond liners. Ice buildup can also be harmful to pond fish, limiting oxygen exchange and putting beneficial bacteria out of balance. For regions with long, harsh winters, the best way to keep even hardy plants and pond fish alive is to move them indoors and shut down your pond completely to save from costly repairs.

In milder climates, most garden ponds will remain operational but they still benefit from a fall cleanup. This seasonal pond care includes cleaning out organic debris, pruning water lilies and other marginal plants, and just checking for adequate water quality to protect against severe damage in case of a cold snap.

You'll Need

• Pond net or skimmer
• Pond vacuum (optional)
• Pond de-icer
• Water treatments (optional)
• Fish food (for fall feeding)
• Pond heater (if necessary)
• Pruners for trimming plants
• Storage for pump and filters
• Thermometer (for monitoring water temperature)

1. Clean the Pond

• Remove any debris such as leaves, sticks, and algae that have accumulated in the pond.
• If you are moving your pond fish and plants indoors, do that now. A garbage can or bucket of fish with a proper aeration kit will overwinter just fine in a basement.
• Use a pond net or skimmer to fish out floating debris. A pond vacuum can help remove gunk from the bottom if your pond has a lot of buildup.
• Ensure that organic material doesn’t decay over the winter, which can create harmful gases that affect water quality.

2. Cut Back Plants

• Trim back any overgrown pond plants like lilies or reeds.
• Remove dead foliage to prevent decomposition during winter.
• If you have tropical plants that won't survive cold weather, consider moving them indoors or into a greenhouse.

3. Shut Down the Pump and Filters (in Freezing Climates)

• If you live in a cold region, turn off and remove the pump and pond filters to prevent ice damage.
• Drain and store the pump in a dry location until spring.
• Clean your filter and any tubing before storage to avoid bacterial growth.

4. Install a De-Icer or Heater

• In freezing areas, installing a pond de-icer or floating heater helps maintain a small hole in the ice, allowing for gas exchange.
• A pond heater can also prevent fish from freezing. Check water temperatures to ensure you’re providing the right environment for your pond.

5. Feed Fish with Cool-Weather Food

• Gradually switch to cold-weather fish food as the temperature drops, usually around 50°F (10°C).
• Stop feeding your fish entirely when water temperatures fall below 40°F (4°C), as their metabolism slows and they become dormant.

6. Monitor Water Levels

• Make sure your pond water is topped off before winter to compensate for any evaporation that may happen during the colder months.
• If needed, add water treatments to keep the water quality stable during the dormant season.

Can Fish Overwinter in a Backyard Pond?

Yes, but it takes some planning. Step one is having a pond that suits your climate. Step two is choosing hardy fish species. Step three requires a fall clean-up and a few add-ins.

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FAQ

Do I have to remove the pump if I live in a warmer climate?

Not necessarily. In regions where temperatures stay above freezing, you can keep your pond pump running year-round. However, it’s still important to do a fall cleaning and regular maintenance to prevent algae blooms and poor water circulation during the winter months.

How do I know when to stop feeding my fish?

Fish feeding should taper off as water temperatures dip below 50°F (10°C). By the time the water temperature reaches 40°F (4°C), it’s time to stop feeding entirely. At this point, fish enter a winter slumber, or a state of torpor. Their digestive systems slow down dramatically and they'll hide out in the deepest areas using organic debris and plant material as a layer of insulation.

How to Winterize a Backyard Waterfall Feature

Learn how to overwinter your backyard waterfalls, water features, and ponds.

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Do all ponds need a de-icer?

De-icers are essential for ponds in areas where freezing temperatures are sustained throughout the winter and a thick layer of ice is a permanent fixture. If your pond is shallow or tends to freeze over completely, a de-icer will maintain an opening in the pond ice to allow toxic gases to escape, protecting your fish and pond health.