In November, pond maintenance shifts from managing algae to managing ice. The biggest threat to your expensive equipment is not dirt or debris—it’s water expansion. When water freezes, it expands by about 9%, and that force is enough to shatter anything from flexible PVC pipes to the quartz sleeve in your UV clarifier.
Your main decision this month is simple but critical: Do you keep your system running, or do you remove and store it?
The "Pull" Method: Total Shutdown for Hard Freeze Zones
If you live in a region that experiences prolonged, deep freezes (Northern, Midwest, or Mountain states), a complete shutdown is the safest and most recommended method. It eliminates the risk of freeze damage and prevents the “overcooling” of your pond.
1. Removing and Storing the Pump
Your pond pump is the heart of your system and the most valuable piece of equipment at risk.
Clean Thoroughly: Before storage, remove the pump from the pond and clean it well. Use a brush to remove algae and scale, especially from the intake screen.
The Submerged Trick: Do not store your pump dry. The rubber seals and gaskets inside the pump need to stay moist to prevent cracking. Place the pump in a clean 5-gallon bucket and fill it with enough water to completely submerge the unit.
Frost-Free Location: Store the bucket in a frost-free location like a basement, heated garage, or utility closet. Freezing will ruin the pump immediately.
2. Draining External Plumbing and Filters
Any equipment located outside the pond, or plumbing that runs above ground, must be completely drained.
Filters and Pressure Vessels: Disconnect all hoses, remove the lid, and let all water drain out. Store filter media (like bio-balls or sponges) indoors, or simply clean the filter housing and leave it open to air dry completely.
UV Clarifiers: These are extremely fragile in cold weather. Remove the entire unit, take out the UV lamp, and remove the quartz sleeve. Store all components indoors. A single drop of frozen water inside the sleeve can crack the glass.
Drain Lines: If you have rigid or semi-rigid pipes, ensure they are emptied. Blow out the lines with a shop vac set to ‘blow’ to clear any trapped water.
The "Run" Method: Circulation for Mild Zones
If you live where freezing is rare or brief (e.g., the Deep South, Coastal California, Pacific Northwest), you may choose to keep a reduced system running.
The Waterfall Ice Dam Warning
The greatest risk when running a waterfall in winter is the ice dam. As the waterfall splashes, ice builds up on the rocks and stream edges. This ice can eventually divert the flowing water outside of the liner and into your yard.
Silent Pond Drain: Because the ice dam forms slowly, you may not notice until the pond has dropped significantly, causing your pump to run dry and burn out.
Daily Monitoring: If you choose to run your waterfall, you must check it daily during cold snaps for any signs of water diversion.
Raising the Pump (Crucial for Fish)
If your pump is running, you must ensure it does not circulate the deepest water.
Avoid Overcooling: Your fish are resting in the deepest part of the pond, which is the warmest layer (around / ). If your pump is on the bottom, it will pull this warm water up to the surface, cooling the entire pond and stressing the fish.
Placement: Raise the pump onto a shelf, a cinder block, or a bucket so that it is running no deeper than about 12 to 18 inches below the surface.
The Safe Alternative: The Power of Aeration
Regardless of your climate, an aeration system is the safest, most effective way to ensure fish survival during winter.
An aerator consists of an air pump (usually placed on the shore or in a garage) that pushes air through tubing to a diffuser stone placed in the pond.
Gentle Gas Exchange: Unlike a pump, the aerator is placed on a shallow shelf or near the edge. It creates gentle bubbles that keep a small hole open in the ice, allowing toxic gases from decaying sludge to escape and fresh oxygen to enter.
No Overcooling: The gentle rise of bubbles does not disrupt the warmer, life-saving water layer where your fish are resting.
Make your decision this week, before the first hard freeze hits. A little effort now saves hundreds of dollars and a lot of headaches in the spring!
