Best Pond Heater For Koi Fish

1. K&H Pet Products Perfect Climate Deluxe De-icer

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For such a great price, it’s hard to believe that this floating pond heater doubles as a pond de-icer. Although we tested out the 250-W version, you should be able to find the 750 and 1500-W versions as well. Nevertheless, we consider this the best Koi pond heater money can buy. However, while writing this review, our main focus was to find the best pond heater for Koi fish, so we definitely took their needs into consideration when choosing this heater.

After trying it out, we found that this Koi pond heater does its job very quickly. It’s wheel-shaped, which ensures that the heat is evenly distributed. If your fish stay close to it, this is a clear sign that it’s doing a good job of generating heat. A huge bonus is that it’s very safe – it doesn’t heat up to the point where it can harm your fish. If you want a pond heater with a thermostat, look no further. Owing to its internal thermostat, this Koi pond heater will prevent your pond from freezing over.

Depending on what you need, you can easily turn this floating Koi pond heater into a submersible one just by pressing a button. It comes with a 12-foot cord, which you can use to place the device anywhere in your pond.


Pond Deicer For Koi Fish

2. K&H Pet Products Thermo-Pond De-Icer

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If you liked the design of our best Koi pond heater, this one is similar to it, but a lot more economical. It runs on just 100 Watts to de-ice your pond. If your pond is at least 18 inches deep, you can use this heater.

This floating pond heater is also great to use on already frozen ponds because it creates a 12-inch hole in the ice. Through the hole, it gives off heat and also allows harmful gases to pass through. We consider this one of the most suitable pond heaters for Koi fish because it ensures that they stay warm all winter round. It also doesn’t take up a lot of space, allowing them to swim around or under it. The heater is safe and won’t burn them or harm your pond in any way because it’s controlled by an internal thermostat system. This means that it only uses the necessary wattage without overheating, and the device automatically turns on and off.

You’ll also find a 12-foot cord which you can use to place the heater where you please.


 Pond Heater For Koi Fish

3. Laguna 500W PowerHeat De-icer For Ponds

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After trying out large pond heaters, we had to mention this one. This floating pond heater is suitable for ponds of all sizes and we consider it one of the best money can buy. It can heat up and de-ice ponds that are below 20 degrees F and less.

The pond heater’s design is pretty simple. Made of stainless steel, the bell-shaped device runs on 500W and allows even heat distribution. When set up, it will create a small hole on the surface of your iced pond which generates heat and allows gases to escape. On the other hand, the hole elevates oxygen levels in the pond, which is very important. This is a great pond heater for Koi fish, because it does a quick and fast job at creating heat which in turn protects this sensitive tropical breed from freezing to death when the temperature drops.

A super handy aspect is that the heater has an LED light which alerts you when the device is working.


Tetra Pond Heater For Koi Fish

4. TetraPond Pond De-icer

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We recommend Tetra Pond’s de-icer if you’re looking for a more affordable floating pond heater or more specifically, a pond heater for Koi fish.

It runs on 300W and although it’s not as powerful as the other picks on our list, we were still pleased with it. The recommended pond size for this heater is at least 300 gallons, so if you have a small number of Koi fish, it’ll do.

It’s designed to resemble a stone, which goes with any sort of pond aesthetic. This pond heater is especially suitable if you own Koi fish, because it works by keeping a section of your pond ice-free. The hole it creates in the ice serves as a gateway for the escape of toxic underwater gases. On the other hand, your Koi will highly appreciate this little space, since this species tends to come up for air.

This pond heater for Koi fish has a built-in thermostat which helps save you energy because it turns off when the time is right. It comes with a 15-foot cord, so you can place it practically anywhere.

Pond Heater For Koi Fish

5. Farm Innovators Model P-429 Submersible Pond De-Icer

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If you own a smaller pond between 300 to 600 gallons, this submersible pond heater is a great choice. It runs on an impressive 1500W and despite its expensive price, we definitely consider it worth the money.

It’s a great pond heater for Koi fish because of its design. The heater has a ring cage surrounding it and it creates a decently-sized hole in your pond’s ice. While your pond warms up, the harmful gases trapped beneath the ice will escape through the hole.

The heater is perfectly safe and won’t harm your fish or plants. Because it’s thermostatically-operated, it knows when to turn on and off on its own, saving energy. A 10-foot cord comes with the heater, too.

What does a pond de-icer do?

The main purpose of a de-icer isn’t to raise the water temperature of a pond; during winter, a pond is bound to be covered with a layer of ice. In this state, a lot of toxic gasses created by plant decay and fish waste can’t escape the pond – which is where the de-icer comes in. Its main purpose is to create a hole in the ice, allowing these gasses to escape and keeping your water safe and healthy for your fish.

What’s the ideal Koi fish water temperature?

The most ideal temperature for Koi fish should range between 59 and 77 degrees F (15-25 degrees C). If their water temperature drops below 10 degrees C, their immune systems grow weaker. It’s also very important that their water isn’t too hot, because less oxygen is present in warmer water.

How to heat a Koi pond


Next to heaters and de-icers, there are other ways to heat a Koi pond:

Using an in-line electric heater
This heating system can be installed hand-in-hand with your pond’s pipework. If you have a pump for your pond, you can set up this system with zero problems. First, the pump transfers the water into a so-called heating chamber. After the water is heated, it goes back into the pond.

Using a heat exchanger
This expensive method is used to heat up super large ponds that can hold several thousands of gallons. The pond water is pumped into the heat exchanger where its temperature is elevated. When heated, the water flows back into the pond. Even though this system is very efficient, its setup is complicated – you’ll need a professional’s help.

What to look for in a Koi pond heater


Most pond heaters for Koi fish have built-in thermostat systems which detect drops in water temperature. Owing to that, they’re programmed to start up and shut down on their own. Investing in a pond heater with a thermostat will help you save money on electricity bills in the long run.

Should you get a floating pond heater or a submersible pond heater? Why not get one that doubles as both instead? Each have their own benefits. While floating pond heaters can melt ice and create holes which supply your pond with oxygen, submersible pond heaters do a much thorough job at generating heat.

We’ve already written on the importance of fish tank heaters and being able to rely on one while you’re away or not able to monitor your aquarium. The same goes for ponds.

Do your research on pond brands. It’s always better to spend a bit more money on a heater you can rely on, than to opt for a product you’re unsure about because you want to save money.