Fluval E Series Heater

Written by Kmuda. Posted in Heaters






* Innovative electronic heater for fresh and saltwater aquariums
* Advanced aquarium heater detects abnormal or non-optimal conditions
* Heater microprocessor monitors and displays aquarium water temperature


The most technologically advanced submersible aquarium heaters available today. Fluval E Series heaters employ an advanced digital microprocessor to continuously monitor and display aquarium water temperature. Internal thermal sensor continuously samples aquarium water temperature for greater accuracy and reliability. Innovative color-coded temperature alert feature changes LCD screen color if aquarium water temperature varies from the pre-set temperature (Green = Safe Zone, Red = High Temperature Alert, Blue = Low Temperature Alert). Easy-to-use adjustment lever allows precision temperature settings in 0.5° increments and integrated heater guard offers advanced protection for fish and invertebrates. For fresh and saltwater aquariums.



•Electronic Technology: Electronic monitoring system, thermal sensor, and LCD temperature display
•Precise Temperature Setting: With the easy to use adjustment lever, the temperature can be precisely set in 0.5° increments.
•Advanced Safety: The integrated fish guard offers advanced protection. Fish and invertebrates cannot come into direct contact with the heater core. The heater is protected against shocks from large fish.
•Mounting Bracket: The heater easily clips on or off of the slim line mounting bracket or can be vertically adjusted for precise placement. The included adapter provides the option of side glass mounting when traditional rear glass mounting is not possible.


Model Length Max. Aquarium Size
50W 10" up to 15 gallons
100W 11-3/4" up to 30 gallons
200W 13-3/4" up to 65 gallons
300W 13-3/4" up to 100 gallons

Downloadable Fluval E Series Heater Instructions PDF.
(Requires Adobe Acrobat Reader 4.0 or later - get it here for free)

Please click on "More Information" for directions for use.

Fluval E Heater Review

by Kmuda


Finding a good heater is becoming more and more difficult these days. Due to the habit of Marineland Stealths exploding and their subsequent recall I needed new heaters for my Oscar Tank. Being an Oscar tank, use of the Eheim Jager heaters was not an option as they are a glass heater (and, for some reason, Heater Guards are not available). While there are various titanium heaters on the market, research identifies few of them get decent reviews and those that do are generally very expensive. This left me with two basic options, a Fluval E or a Rena Smartheater (note: this was written before the Aqueon Pro was released, it is a very viable option for an Oscar tank). Having had such historical good luck with the Fluval Tronic Heaters (albeit not so good luck with the Fluval M), I decided to go ahead and try the Fluval E.

I made a good choice. I am happy.

Don't let the "high technology" marketing scare you away. The technology is used to make things simple, not complicated. I've never owned a heater that was easier to "set" a desired temp. The LCD display makes it very simple to identify the current temp and the fact that the display changes colors makes it very simple to determine temperature safety at a glance (Red = Too Hot, Green = Just Right, Blue - Too Cool).

I've been using this heater for several years and have not experienced any issues. Many of the design concepts associated with the Fluval Tronics were transferred over to the Fluval E and I've had a Fluval Tronic in use for almost 20 years. If the Fluval E is anywhere near as reliable, it's worth every penny.

As for comparison to an Eheim Jager? The quality of glass used in the Eheim is obviously much higher. The Fluval E glass quality would be closer to a Fluval M. However, the Fluval E does come packed inside a very sturdy heater guard and has stood up well to my Oscar's attempts to rearrange the tank.

The Fluval E is an excellent choice for an Oscar Tank.


  • Steady Temperature: Heater maintains a very steady temp. I have only a single 300 watt Fluval E running on a 120 gallon tank and am having no problems maintaining a steady 80 degree temp.
  • Ease of Use: I've never had a heater that was easier to set and monitor. To adjust the temp, simply move a level at the top of the heater left or right (to adjust up or down) and the LCD display will identify your selected temperature.
  • LCD Display: Easy to read display serves multiple functions. Not only does it eliminate the need for a secondary thermometer (which are another hazard in an Oscar Tank) it also allows you to notice, at a glance, temperature safety via color changes in the display.
  • Heater Guard: Any heater placed into an Oscar tank must be indestructible (or close to it). This is either accomplished via the heater being constructed of non-breakable material or via protection of the glass components by a sturdy guard. The Fluval E glass components are well packaged inside a sturdy heater guard.


  • Cost: Heater cost more than standard heaters but is lower in cost than quality Titanium Heaters.
  • Unplug During Water Changes: This should be done for any heater, even ones identified as "self shutoff". However, I would consider it an absolute requirement for a Fluval E Series Heater.