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Best Pond Heater & De-Icer (Pond Heating Guide 2021)

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A pond heater can be a crucial component of your outdoor pond during winter.

And it may be necessary if you have pond fish!

But, different types of pond heaters and de-icers perform different functions.

Let's look at the 6 best pond heaters and de-icers on the market today and determine which one is right for your specific pond's size and needs.

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Best Pond Heater & De-icer Reviews

Comparison Chart

Description Pond Size Price
K&H Pet Products Thermo 3.0 Pond Deicer, 100w K&H Pet Products Thermo 3.0 Pond Deicer, 100w Up to 1000 gallons SEE PRICE »
Danner Manufacturing Floating Pond De-Icer, 120w Danner Manufacturing Floating Pond De-Icer, 120w Up to 1000 gallons SEE PRICE »
TetraPond Floating Pond De-Icer, 300w TetraPond Floating Pond De-Icer, 300w 250 – 500 gallons SEE PRICE »
Catalina Submersible Pond Heater, 1000w Catalina Submersible Pond Heater, 1000w 150 to 400 gallon SEE PRICE »
Farm Innovators Premium Floating Pond De-Icer, 1250w Farm Innovators Premium Floating Pond De-Icer, 1250w up to 600 gallons SEE PRICE »
Allied Precision Floating Pond De-Icer, 1500w Allied Precision Floating Pond De-Icer, 1500w 1500-2000 gallons SEE PRICE »

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K&H Pet Products Thermo 3.0 Pond De-icer, 100w

The K&H Thermo 3.0 is an energy-efficient way to heat a pond up to 1000 gallons, costing an average of $30 less per month than larger wattage models!

This pond de-icer keeps a hole in the icy surface of your pond without getting too hot, so you don't have to worry about it burning a hole in your pond liner.

This low-wattage heater is typically enough to keep a small hole in the ice to allow for proper gas exchange and to keep your pond water oxygen-rich. Though if you stock a lot of koi or other pond fish, you may need a larger model.

Specifications

Heater size: 100 watts
Pond size: Up to 1000 gallons
Power cord length: 12 feet
Dimensions: 12x12x4 inches
Warranty: 1 year limited

Pros

  • Long power cord
  • The thermostat helps reduce heating time, save electricity, and prevent liner burns
  • Energy efficient

Cons

  • Low wattage – may need multiple units or a higher wattage model if you stock a lot of pond fish or have a larger pond
K&H Pet Products Thermo 3.0 Pond De-icer, 100w

K&H Pet Products Thermo 3.0 Pond De-icer, 100w

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Danner Manufacturing Floating Pond De-Icer, 120w

The Danner Manufacturing Floating Pond De-Icer is an energy-efficient, low-wattage pond de-icer made of high-impact ABS plastic.

This de-icer will not harm your pre-formed or flexible pond liner and comes with an extra-long 18-foot power cord which is great if you don’t have a power supply right next to your pond.

While the manufacturer recommends this for ponds up to 1000 gallons, I’d look at using a higher wattage model if your pond has koi or is over 250 gallons, just to be safe.

Specifications

Heater size: 120 watts
Pond size: Up to 1000 gallons according to the manufacturer (I’d personally look at a larger wattage model if your pond is over 250 gallons)
Power cord length: 18 feet
Dimensions: 12x12x4 inches
Warranty: 1 year limited

Pros

  • Extra-long power cord
  • Fixed thermostat helps reduce heating time and save electricity
  • Energy efficient
  • Will not harm your liner

Cons

  • Low wattage – may need multiple units or a higher wattage model if you stock a lot of pond fish or have a larger pond
Danner Manufacturing Floating Pond De-Icer, 120w

Danner Manufacturing Floating Pond De-Icer, 120w

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TetraPond Floating Pond De-Icer, 300w

The TetraPond Floating Pond De-Icer is an excellent, thermostatically controlled heater that will create a hole in your pond’s icy surface to allow for proper gas exchange.

This de-icer features a natural stone look that will blend into your pond’s surroundings. It also features an energy-efficient thermostat that will automatically shut the power off when it’s not needed to save on electricity costs.

The 15-foot power cord is an excellent addition, especially if you don’t have a power outlet near your pond or water garden.

And unlike most de-icers, this model features a lengthy 3-year warranty, which means you can buy with confidence.

Specifications

Heater size: 300 watts
Pond size: 250 – 500 gallon pond heater
Power cord length: 15 feet
Dimensions: 11.3x6.4x6.9 inches
Warranty: 3-year limited

Pros

  • Long warranty
  • Extra-long power cord
  • Natural stone-look

Cons

  • While it's not a bad pond heater for koi ponds, you may need a higher wattage de-icer that makes a larger hole for better gas exchange
TetraPond Floating Pond De-Icer, 300w

TetraPond Floating Pond De-Icer, 300w

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Catalina Submersible Pond Heater, 1000w

The Catalina Submersible Pond Heater with thermostat is used to heat your cold pond water. This is ideal if you need to heat a pocket of water in your pond for your fish to hibernate. Keep in mind, you’ll want at least one heater for every 400 gallons of pond water for best results.

This outdoor pond heater features a guard made of durable plastic to help protect fish from the heating element. And it’s made of non-corrosive titanium alloy, making it perfect for saltwater applications, as well as handling PH fluctuations in your pond.

The built-in thermostat allows you to heat your pond between 72 and 93-degrees F and will automatically shut off when the desired temperature has been reached.

Again, this model is slightly different than the other pond heaters as it’s more designed to heat pond water than to create a hole in the ice. If you live in an extremely frigid environment, then combining this model with a de-icer will help your fish to hibernate comfortably and ensure they get the proper gas exchange needed for survival.

Specifications

Heater size: 1000 watt pond heater
Pond size: 150 to 400 gallon
Power cord length: 6 feet
Dimensions: 14x.5 inches
Warranty: 1 year limited

Pros

  • Heats cold water allowing for a comfortable hibernating environment for pond fish
  • Automatic shut off switch
  • Won’t corrode in saltwater tanks or ponds
  • The heating element guard keeps fish safe

Cons

  • Short power cord length
  • Will need multiple heaters if you have a larger pond, which can raise the operating cost
  • Depending on pond size, you may still need a floating de-icer to ensure the pond surface doesn’t completely freeze over, blocking gas exchange
Catalina Submersible Pond Heater, 1000w

Catalina Submersible Pond Heater, 1000w

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Farm Innovators Premium Floating Pond De-Icer, 1250w

The Farm Innovators Premium Pond De-Icer is a fish and plant-friendly heater that’s perfect for ponds up to 600 gallons according to the manufacturer (though I’ve used several 1250-watt models in ponds up to 1500 gallons successfully).

This heavy-duty pond de-icer is thermostatically controlled and constructed of cast aluminum for energy efficiency and safety.

It is fish and plant friendly and comes with an industry-leading 3-year warranty.

Specifications

Heater size: 1250 watts
Pond size: up to 600 gallons according to manufacturer
Power cord length: 10 feet
Dimensions: 4.5x7.5x7.5 inches
Warranty: 3 year

Pros

  • Long 3-year warranty
  • Cast aluminum design for efficiency and safety
  • Safe for fish and plants, making it a great koi pond heater

Cons

  • Could use a longer power cord (though an extension cord will help alleviate this “short” coming – pun intended!)
Farm Innovators Premium Floating Pond De-Icer, 1250w

Farm Innovators Premium Floating Pond De-Icer, 1250w

Price:
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Allied Precision Floating Pond De-Icer, 1500w

The Allied Precision Pond De-Icer is a powerful 1500-watt heater that is perfect for larger ponds.

This de-icer will keep a 100 to 300-gallon pond completely ice-free. And will work perfectly to keep an ice hole open and allow for proper gas exchange for ponds up to 2000 gallons.

This de-icer will plug right into a standard 110-volt power supply and is thermostatically controlled with an automatic shut-off.

The one downside to this de-icer is the extremely short 6-foot power cord. If this is an issue for your pond setup, you’ll just have to use an extension cord which can be found for pretty cheap.

Specifications

Heater size: 1500 watts
Pond size: 1500 - 2000 gallon pond heater (100 - 300 gallon pond heater if you want it completely ice-free)
Power cord length: 6 foot
Dimensions: 9x8.8x6 inches
Warranty: 1 year

Pros

  • Powerful 1500-watt electrical heater
  • Large pond heater (up to 2000 gallons)
  • Can keep smaller, 100 to 300-gallon ponds completely ice-free
  • Automatic shut-off

Cons

  • Extremely short power cord length
  • Short, 1-year warranty
Allied Precision Floating Pond De-Icer, 1500w

Allied Precision Floating Pond De-Icer, 1500w

Price:
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Pond Heater Buyers Guide

What is a Pond Heater & De-Icer?

When the winter months come around, the water temperature in your pond can be controlled with a pond heater and de-icer. These heaters also help maintain a hole in the icy surface of your pond. This is extremely important for the safety of your fish. In fact, it's so important that pond de-icing products are a top mention in our handy guide to keeping pond fish alive in winter (check it out!).

Let’s look at the 3 major benefits that pond heater/de-icers provide.

Increase Pond Water Flow

Firstly, the de-icer will free some water of ice and subsequently increase the temperature of the water. Even if the rest of the water is under ice, this will still improve the water flow for the entire pond.

did you know Did you know...

The energetic molecules of the heated water will move around the pond to the less energetic molecules of the cold water, allowing for a natural flow while oxygenation improves. In other words, the warmer water reaches the colder water and provides a natural flow.

For ponds that don’t have a waterfall or pond pump, this oxygenation and flow can be essential for the pond's ecosystem.

Faster Thaw

With specific areas of the pond free from ice, thawing will be a breeze. Rather than spending a whole weekend breaking up the ice, the heater will do most of the work. As the sun shows its face more frequently, your heater will complement the rising temperatures, and the ice will gradually disappear - a small benefit, but hey, a benefit nonetheless.

Allow for Proper Gas Exchange

Did you know that gas exchange is impossible when a pond freezes over? What this means is that the oxygen in the air can’t penetrate the water. As we’ve already learned, a de-icer will allow for a hole in the ice, which boosts oxygen levels in even the coldest of months.

Why is this important? To put it bluntly, your fish may become ill and die without dissolved oxygen in the pond. As well as falling oxygen levels, carbon dioxide levels will rise because there's no escape point. With a simple hole in the ice, so oxygen is allowed in and carbon dioxide out, your fish will not only survive the winter but thrive in it too.

Learn more about why you may want a de-icer for your fish pond, plus a few tips and tricks to get the most out of your heater with this short video.

Types of Pond Heaters

When looking to heat your pond, there are two main types of heaters to consider.

Floating Pond De-Icers

If you’re looking for an effective heating solution that’s cheap and simple, then look no further than a floating pond deicer. Rather than increasing the water temperature, the idea with a floating de-icer is to create an opening in the pond’s icy surface for gas exchange. By creating a hole in the ice, your fish can get the oxygen they need to stay healthy.

In truth, everything about these models is simple, from their running costs to set up. Floating pond heaters work perfectly with both large and small ponds (and even those with Koi and other pond fish). If you’re looking for pond temperature control, you can consider combining the de-icer with a submersible pond heater, which we’ll learn about next. But, in most cases, a pond de-icer is all you’ll need.

Allied Precision Floating Pond De-Icer, 1500w

Allied Precision Floating Pond De-Icer, 1500w

Price:
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Submersible Pond Heaters

Submersible pond heaters are designed for larger aquarium-style tanks. However, special pond models have been made which help create a warm pocket of water underneath the surface. Once set up, your little fishy friends will have somewhere to hide out during the winter. While smaller ponds will only require a single heater, larger ponds may require several.

Most manufacturers recommend placing the unit as deep as possible and where the water flow is low. By doing this, it isn’t exposed to outside temperatures, and you won’t lose heat to the surface.

Catalina Submersible Pond Heater, 1000w

Catalina Submersible Pond Heater, 1000w

Price:
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There's actually a third type, an inline pond heater, but the above two types are the most popular, with the floating heater being far and away the most popular.

Which Pond Heater Do We Recommend?

Now that we’ve looked at the two main types of pond heaters, which one do we most often recommend?

In almost all cases, we usually just recommend using a floating pond de-icer. Ultimately, they will provide sufficient oxygenation (the fact that they’re cheap and easy to install are simply bonuses).

TetraPond Floating Pond De-Icer, 300w

TetraPond Floating Pond De-Icer, 300w

Price:
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Buy Now on Chewy

Clicking this link to make a purchase may earn us a commission at no additional cost to you.

Although in-line and submersible pond heaters do their job well, they aren’t necessary for casual pond owners who just want to ensure survival for their fish. Since fish sleep to survive cold temperatures, all you really need to do is ensure a surface opening for oxygen to enter.

If you’ve considered your options and think heating is the way to go, monitoring and adjusting temperatures will be much easier with a digital thermostat, so look for this feature with submersible heaters.

Catalina Submersible Pond Heater, 1000w

Catalina Submersible Pond Heater, 1000w

Price:
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Furthermore, we should note that heating the water too warm can actually be more dangerous to your fish than leaving it cold. Once set up, choose the correct wattage and check the water temperatures regularly.

Finally, a heater can also be combined with a pond aerator during winter for ponds with lots of fish. With the air pump, this has a double benefit;

  • It provides a direct source of oxygen
  • It breaks up the ice
Laguna Aeration Kit for Ponds

Laguna Aeration Kit for Ponds

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What Size Pond Heater/De-Icer Do I Need?

With every de-icer slightly different from the next, we advise checking the manufacturer’s recommendations to prevent future headaches. However, there are some general recommendations we use, as you’ll find out below.

Also, keep in mind that multiple holes in the ice might be necessary for ponds with lots of fish and/or oxygenating pond plants. When these two are present, the gases build quicker, so multiple holes will alleviate the problem.

While assessing your own pond, consider the number of gallons it contains and whether or not it will be used with an aeration system. If you don't know how many gallons your pond is, use our free pond calculator to find out. Here are our general wattage recommendations:

  • Anything up to 250 gallons - Between 100 and 250 watts
  • Between 250 and 500 gallons - 300 watts
  • Between 500 and 1,000 gallons - 750 watts
  • Between 1,000 and 1,500 gallons - 1,250 watts
  • Between 1,500 and 2,000 gallons - 1,500 watts

We should also note that floating de-icers will always be more efficient in shallow sections of water (i.e., near the edge of the pond). As the pond water warms, it will bounce off the edges and become more effective as a de-icer (it also means you won’t have to get your skates on to fix the unit if there are any problems).

Pond Heater FAQs

What Is the Difference Between a De-icer and a Heater?

We’re going to save you lots of confusion… pond heaters and de-icers are the same things!

We understand this may be confusing, but brands just name the product depending on what term they prefer. Don’t fall into the trap of thinking that a ‘heater’ might be more effective than a ‘de-icer’ (or vice versa!). They will both do the same job, and they’re both designed to prevent your pond from turning into a skating rink in the winter.

There are, however, two types of pond heater/de-icers. As we discussed above, these include:

  • Submerged - Normally installed at the bottom of the pond, submerged models will heat the pond’s lowest point. They are perfect for ponds with a depth of fewer than 18 inches as they will provide your fish the warmth necessary for survival. As long as you keep monitoring the surface (because these models may not prevent the pond from freezing over), your fish will stay warm while we’re covering ourselves in blankets inside the home. If the submerged heater isn’t doing a great job alone, it might be worth investing in a floating de-icer too.
Catalina Submersible Pond Heater, 1000w

Catalina Submersible Pond Heater, 1000w

Price:
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  • Floating – As the name suggests, this heater option floats on the surface of your pond, thus keeping an area of the surface clear of ice. To save energy and remain efficient, they operate based on temperature; they won’t run until the water temperature drops below a certain point. While they won’t keep the whole surface clear, there will be a perfect hole for the exchange of gases to occur.
Farm Innovators Premium Floating Pond De-Icer, 1250w

Farm Innovators Premium Floating Pond De-Icer, 1250w

Price:
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Clicking this link to make a purchase may earn us a commission at no additional cost to you.

Do You Need a Heater for a Pond?

Ultimately, fish pond heaters serve three main purposes:

  • To provide oxygen
  • To allow for the exchange of gas
  • To help the fish during torpor

During the winter months, if your pond completely freezes over, it can cause a reduction in the pond's oxygen levels. When this happens, the low-oxygen conditions can be horrific for your fish and their survival. With a heater creating a permanent hole in the icy surface, oxygen will enter your pond, giving pond life the right environment to thrive in.

Related: How to Heat a Pond in Winter (with solar options to save on running costs)

So, do you need a pond heater for winter? While these three purposes are important, they may not be required if you don’t have fish. Even if you do have fish, if the winters don't get cold enough for the surface to freeze over, you still may not have to invest in a water heater. If it’s your first winter in a new home or after installing the pond, we advise keeping a careful eye on the water as winter progresses.

In case you didn’t know, the ‘torpor’ (hibernation) of fish will see them remain at the deepest, warmest point of the pond (see Do Pond Fish Hibernate in Winter? for more information). Assuming they have oxygen, they’ll be happy here. If their torpor is interrupted by a lack of oxygen and a frozen surface, this is where the difficulties begin. For those with Koi, you might consider running a heater regardless because they’re notoriously sensitive to reduced dissolved oxygen levels.

What Is the Running Cost of a Pond Heater?

Earlier, we noted the type of device you should be looking for (in watts) depending on the size of your pond. For those with larger ponds and larger heaters, you need to be ready for the cost associated with this. Depending on your location and how much utilities charge per kilowatt-hour, we could be talking about $75 each month.

You can heat your pond cheaply with a low-wattage garden pond heater. Or better yet, pond aerators are an alternative that creates a hole in the ice but without the same price tag.

Thanks to the development of efficient air compressors, these types of units can often run off just 12 watts when pushing air to the diffuser. Although each unit will vary, this means you could be saving between 85% and 99% in electricity.

As the air weakens the ice, a hole will form, and your pond will enjoy all the benefits we’ve already discussed. The aerator both circulates the pond water and adds oxygen to keep your pond fish happy.

Laguna Aeration Kit for Ponds

Laguna Aeration Kit for Ponds

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How Do I Install a Pond Heater?

To install a submersible pond heater, place it in the water at a specified depth, plug it in, and turn it on. A floating de-icer is equally as simple - place the heater near the edge of your pond, plug it in, and turn it on.

Of course, you will want to read the manual that came with your specific heater for more specific instructions. But, it isn’t a complicated setup process, and anybody can DIY the install in minutes. However, pond heaters are electrically powered, so you may have to install an outlet (or have it professionally installed) near your pond.