Which pond de-icers are best?
One of the best ways to keep your fish safe and healthy during the winter months is by preventing your pond from completely freezing over. A pond de-icer saves you and your fish the heartbreak of “winterkill” caused by a combination of low oxygen levels and dangerous gases trapped beneath the ice as temperatures dip below freezing.
Before purchasing a pond de-icer, you should consider important factors like pond size, durability, cord length, and whether a submerged or floating de-icer is better. Our buying guide explores all these factors and offers our product recommendations at the end, such as the professional-grade stainless steel Kasco Marine Lake and Pond De-icer.
What to know before you buy a pond de-icer
Pond size as measured in gallons and the severity of your winters determines the size of de-icer you need. As a basic rule of thumb, you need one watt of power for every gallon of water in your pond (e.g., 300 watts for 300 gallons).
Your pond de-icer should be durable enough to stand up to harsh conditions and the lower limits of temperature in your climate. Some models can weather -20°F while others struggle if temperatures dip below 20°F. Stainless steel stands up best to corrosion and cracking, followed by cast aluminum. While plastic is the least durable, it doesn’t get quite as hot as metal de-icers, which can damage ponds with plastic liners.
If you choose a floating de-icer, you may want to consider its appearance since it will be visible. Some de-icers are made to mimic natural stone, while others may stand out in the pond like a sore thumb.
Submerged vs. floating
- Submerged: A submerged de-icer may be more visually appealing, since it doesn’t distract from your pond’s aesthetic. Submerged de-icers are typically more energy-efficient and help circulate water more effectively. Installation for a submerged de-icer is usually more complicated, since it must be hung or mounted.
- Floating: A floating de-icer floats on the pond’s surface. While it’s less energy-efficient and more expensive to run than a submerged de-icer, it’s often more effective in very low temperatures. Installation is simple: just plug the de-icer into a power source. The float in some models can be removed, allowing you to submerge the de-icer if desired.
What to look for in a quality pond de-icer
Cord length and type
Since most manufacturers advise against using an extension cord, a de-icer’s power cord length is an important feature. Cord length varies from 10 feet to more than 100 feet. Measure carefully from your power source to your pond before making a purchase. Wire-wrapped cords are desirable in harsh winter climates, since they hold up best in low temperatures.
Some models include a helpful LED display that shows you at a glance whether or not the de-icer is powered on. Check your de-icer regularly during the winter, since these products are somewhat notorious for their shorter lifespan.
While a de-icer doesn’t have a traditional thermostat that gauges temperature, many models offer a power-saving feature that turns the de-icer on and off as needed based on water temperature.
How much you can expect to spend on a pond de-icer
Budget de-icers for small tanks or ponds start at $40, but you should keep in mind that low-end models are notorious for lasting just one or two seasons. Mid-range models offer warranties, coverage for larger ponds, longer cords, and cost between $50-$100. Submersible professional-grade options meant for boats and large bodies of water can cost upward of $600.
Pond de-icer FAQ
Q. Do I need a pond de-icer if I have an aerator or waterfall?
A. If you’re already using an aerator to help oxygenate your pond, you may not need a de-icer unless your winters are very harsh, which is good news, since aerators are less expensive to purchase and run. Likewise, if you have a waterfall that runs during the winter, you don’t need a de-icer.
Q. How should I position my de-icer in the pond?
A. Position your de-icer in a shallow area of the pond that you can comfortably access for installation. Your de-icer reflects heat off the sides and bottom of the pond, so a shallow area allows it to work more efficiently.
What are the best pond de-icers to buy?
Top pond de-icer
Kasco’s Marine Lake and Pond De-icer
Our take: Professional-quality, stainless steel de-icer that can easily manage larger ponds.
What we like: High-quality materials and construction. Simple setup and instructions. Several power cord length options up to 100 feet. Able to maintain a 95-foot diameter ice-free circle of water.
What we dislike: More expensive than other options. Heavy to lift. Must be mounted rather than hung to prevent wire breakage.
Where to buy: Sold at Amazon
Top pond de-icer for the money
Our take: Affordable, attractive option that’s energy-efficient and great for ponds up to 300 gallons.
What we like: Natural-looking faux stone finish. 15-foot cord. Energy-efficient and keeps pond de-iced down to -20°F.
What we dislike: May only last one or two seasons.
Where to buy: Sold at Amazon
Worth checking out
Our take: Durable, cast-aluminum construction that’s great for smaller ponds or tanks.
What we like: Efficient at de-icing ponds or tanks up to 600 gallons. Includes wire-wrapped 10-foot cord.
What we dislike: Some reports of units failing after only a few uses.
Where to buy: Sold at Amazon
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Noelle Ihli writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
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