Fishes tend to be very fussy when they have to live in a closed ecosystem. But in all honesty, they can’t be blamed because they are quite delicate. Most parameters need to be optimum for them to thrive and remain healthy.

For instance, they need enough heat for their survival and growth. The temperature under the ocean or freshwater is quite different from what we feel here. So, it is essential that you get one.

You don’t have to get the best aquarium heater in the market, but it is necessary to get one that is suitable for your fishes and plants in the tank. Heaters are known to perform efficiently in maintaining the aquarium’s temperature.

It is a known fact that fluctuating temperatures cause stress in humans. This applies to aquatic plants and fishes as well. If the aquarium faces changing temperatures, it will shock the fish.

Therefore, it is vital to keep the temperature at a specific level. But this depends on the types of fishes that you will be keeping. For instance, a fish that has lived in cold water can survive in low temperatures.

Whereas, a tropical fish requires a higher temperature to thrive in. For this reason, you need a proper aquarium heater.

In this Eheim Jager Heater review, we will talk about a product that has most of the necessary features mentioned above. Also, you will get to know the pros and cons.

Based on this, you can decide if the product is worth the bucks!

Eheim Jager Heater Review


Check Price & Reviews on Amazon

Things to Consider Before Buying

Unlike us, fishes are incapable of controlling their body temperatures. So they depend on the water to sustain their body heat. Therefore, you must keep the water temperature in your aquarium as balanced as possible.

The heater maintains a stable temperature by operating a thermostat that is built inside of it. Changes in the water temperature can prove fatal in the long run.

Keeping it at a consistent level mimics the oceanic environment as the sea does not change its temperature quickly.

Not Suitable for Scaleless Fish

Generally, there are 4 or 5 types of heaters. The Eheim Jager is a submersible heater. So, this device is usually placed under the water. It should be kept close to the filter inlet so that it will be able to heat the water uniformly as it comes back to the tank.

Submersible heaters are more beneficial than immersible ones. However, this device is not built with a heater shield. The shield is known to protect different types of fish if they swim close to the heater.

While a scaly fish can handle the heat the device emits, a scaleless fish cannot. Fishes like puffers, catfish, and loaches can fatally injure themselves if they touch the heater.

So if you are planning to keep scaleless fishes, then we suggest you buy another heater such as the Fluval E Electronic Heater. It has an integrated guard built around the heater, which will protect the fish from being hurt.

Presenting The Eheim Jager Aquarium Heater

Save $2.49
Product Features
6,059 Reviews
Product Features
  • Heater is meant for Tanks between 159-264 Gallons.
  • Size of Heater is 20” X 1.4” Diameter
  • Fully submersible, will automatically turn off when water level dips too low.
  • Thermo safey control protects against running dry.
  • Made of shock resistant and shatter proof glass for fresh or marine water.

The submersible Eheim Jager comes in different ranges of lengths and watts. But because of its size, you might have to keep it horizontally in your aquarium.

Although, if you place it vertically in the tank, the dial will be close enough to the surface of the aquarium. This will make it easier for you to fix the thermostat.

Furthermore, it features a TruTemp dial. The dial has a straightforward, simple setting that will allow you to set the temperature as you want. But you need to repeat the calibration process for a while after the first setup.

There is an on and off switch through which you can observe if the device is working or not. Even if there is a dramatic change in the temperature, the heater will remain intact.

Furthermore, there are two safety features, which include a shock-resistant, shatterproof temperature glass, and an automatic shut down option if the level of water drops below normal.

However, the heater dominating the market now is the Fluval E Electronic. Unlike Eheim Jager, it has a mounting clip for you to mount it at different angles. It also has a microprocessor and an LCD.


  • Shock resistant and shatterproof temperature glass
  • Able to set your desired temperature with TruTemp
  • Automatic shut down feature if the water level goes down below
  • Offers versatility with different lengths and watts


  • Takes time to finish the calibration process
  • Hard to place it vertically
  • Not safe for scaleless fish
  • The dial is a little tricky to turn

Check Price & Reviews on Amazon

Eheim Jager Heater Review: Features and Benefits

Precise Temperature Control

The manufactures of this heater designed the product to be manually adjusted. With the help of TruTemp dial, the temperature can be changed from sixty-four to ninety-three degrees Fahrenheit.

Once it has been calibrated, the device will maintain a stable and constant temperature. This is crucial for the well-being and survival of inhabitants in the aquarium that are sensitive to the tiniest change in temperature.

Fully Submersible

The heater has a dry run safeguard while being completely submerged in the tank. This increases the efficiency of the heating process.

Moreover, the heater will automatically shut down when the level of water drops below normal. This priceless feature decreases the risks of electrocution and broken glass. It is also shock-resistant and shatterproof.

Easy Installation

It is effortless and pretty straightforward to set up the heater. The brackets and suction cups isolate and protect the glass of the planted tank. Besides, the equipment does not allow much space for fishes to get caught in between other objects and the heater.

The adhesive cups are flexible because you can place the heater anywhere as long as it is close to a high-flow zone. Moreover, the ideal location for a submersible heater is next to the filters.

Additional Advise: Buy an aquarium heater controller.

Final Words

This heater is among the most efficient and accurate heating system. Even though the process of calibration requires patience and skill, it will be completely worth it in the end.

The variety of features that this device offer makes the cost completely reasonable. Its dry-run safeguard feature sets it apart from other products. Furthermore, it is also shatterproof and thoroughly water-resistant.

We hope you found our Eheim Jager Heater review informative. If you are still skeptical, make sure to read again and enlighten yourself!

Check Price & Reviews on Amazon

Similar Posts