Fluval E Series Heater Review: Is It For You?

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If you are looking for one of the top-end aquarium heaters that are feature-rich, you can’t go wrong with the Fluval E Series heaters. But do they deserve the top spots in the best aquarium heaters list? Are there any flaws? Read on till the end to find out!

What I Like About The Fluval E Series Heater:

The Fluval E Series Heater has a handy LCD display which I like the most. The heater’s LCD screen displays the water temperature in real-time and communicates the reading in Celsius or Fahrenheit. 

The most helpful feature is that it comes with a color-coded alert system.

Here’s an example of the color the LCD screen in the Fluval E Series heater would display based on the temperature:


The LCD screen will change color to let you know about the safe zone temperature and the high/low fluctuations. 

The temperature reading will change color if the water temperature varies +/ – 2° F or more from the pre-set temperature.

So whether you are just passing by your aquarium or before sleeping, you can just take a quick look at the color of the heater’s LCD screen and have that peace of mind. You don’t need to worry if it’s green, as it indicates the safe zone.

But if the color is red or green, you can investigate and solve the issue quickly to prevent any potential damage related to low or high temperatures. That’s helpful.

Another cool thing I like about the Fluval E Series Heater is they come with a protective casing – heater guards.

A heater guard is a cover (usually made of plastic) that encloses your aquarium heater. It helps in protecting the heater glass from any physical damage. Also, it prevents the fish from coming in direct contact with other tank decors and the fish. 

Even though the heater burning issue with fish or tank decorations is not so common, we still can’t rule out the possibility. So it’s better to be safe than sorry and have an aquarium heater guard. 

With Fluval E Series Heaters, you don’t have to spend anything extra for the heater guards, as it already comes along. Hence, that’s an added benefit you get!

What I Don’t Like About The Fluval E Series Heater:

The first thing I dislike about the Fluval E Series Heaters is their cost. For instance, the Fluval E300 (A 300 Watt Fluval E Series Heater) is more expensive than other best aquarium heaters on the market, like the Eheim Jager Aquarium Thermostat Heater 300 Watt.

But you also get the added benefit of the Fluval E Series heater, which is missing in Eheim Jager. 

In Eheim Jager, you only get an on/off indicator light and no heater guard. On the other hand, Fluval E series heaters have an advanced LCD with a color alert system and a heater guard. 

So the Fluval E Series Heater is worth the price if you are willing to spend for the added benefits you get in return.

Check The Current Price Of Fluval E Series Heaters Here (on Amazon). 

Another problem that could be an issue with Fluval E Series heaters is the flow rate issue. If you don’t set up the heater properly, you will probably keep receiving an “LF” warninga Low Flow rate issue in the LCD display screen, which you might not like.

One of the important criteria for setting up the Fluval E Series heater is to locate it correctly in your tank, in an area with good enough water flow. The water flow should be directed towards the top side of the case enclosing the heater, as the sensors are located in that area. 

The aquarium heaters generate heat using electrical energy. And as the heater starts functioning, the surrounding water gets warmed up and comes to the required temperature we want. 

Hence, it is important to have proper water circulation in the tank to get a constant temperature throughout your tank. Otherwise, areas of hot and cold pockets will arise in the tank water, which is not great for the fish.

Aquarium heaters are pretty compact in size compared to the amount of heat they produce. So it is essential to have adequate heat exchange in their surroundings or else they would get damaged.

Now, most normal aquarium heaters are not equipped with such advanced sensors that can tell us about the low flow warning. But with Fluval E Series heaters, you can get this opportunity.

So even though receiving an LF warning can be an issue, it’s actually the specialty of this heater. And by setting the heater near a high water flow area (near the outflow area of a powerhead or filter), you shouldn’t face any problems.

Pros & Cons

Reputed BrandRelatively Expensive
LCD Display ScreenLow Flow Rate Warning
Alert System With Color Indications
Heater Guard
Lever On Top To Control Temperature

What’s Included?

  • You get the Fluval E series heater.
  • Brackets for mounting it on your fish tank glass.
  • And an instructive guide.

The Mounting brackets are independent of the Fluval E series heaters. So you can separate the heater from the bracket as per your needs.

The heater guard comes integrated with the heater itself. So all the parts of the heater are pretty much set up already. You simply need to find a proper location in your tank, install it and start using it.

The Fluval E Series heater comes factory set at 25°C (77 °F). However, if you prefer to set a different water temperature, you can easily set and control the temperature using the top lever. 

You can push the lever right or left; with each push, the temperature will increase or decrease by 0.5-degree intervals (in °C or °F). Once you have made the necessary adjustments, you can finally release the lever. Here’s a link to the instruction manual for your additional reference.

Features & Specs:

  • Fluval E Series heaters are fully submersible and have a waterproof design that allows you to place them in your fish tank without worry.
  • The Fluval E Series heater also includes an integrated guard that prevents fish and other tank species from directly contacting the heater core. 
  • Moreover, its glass sleeves are made so the large, curious fish in your tank can’t cause any physical damage.
  • A Lever is present at the top of the heater that allows adjusting the temperature in increments of 0.5°C or 1°F.
  • You also get 5 years of warranty with these heaters. 
  • The Fluval E series heaters come in three variants: Fluval E100, Fluval E200, and Fluval E300.
Fluval E Series:Fluval E100Fluval E200Fluval E300
Watts:100 W200 W300 W
Tank Size:Up to 30 GallonsUp to 65 GallonsUp to 100 Gallons
Price:Check HereCheck HereCheck Here

Final Thoughts – Is Fluval E Series Heater For You?

Fluval E Series Heater Is The Right Choice For You If:

  • You are an aquarium hobbyist and love to try new things with cool features in your main display tank
  • You are a fan of the Fluval brand and enjoy using their products.
  • You are looking for one of the best aquarium heaters with cool additional features.
  • You are ready to pay for the price, which is relatively expensive considering aquarium heaters for all the features you get.

However, the Fluval E Series Heater Is Not For You If:

  • You don’t want additional features like an LCD display screen or the alert system from an aquarium heater. (Means you are okay with the simple heaters)
  • You are not ready to pay a higher price for an aquarium heater.

So I hope you found this Fluval E Series Heater review helpful. Please share this post with others if you have found any value. That’s it; see you in my next post. Till then, have a great fishkeeping day!