Best Heaters For Nuvo Fusion 20 Aquarium

If you recently purchased the Nuvo Fusion 20 all in one aquarium, you might be looking to add a new heater that will work well and fit in the tank.

The Innovative Marine Nuvo 20 is a great nano tank and is one of the more popular choices. Although this tank comes with a built-in filtration section and return pump, it does not include a heater with the kit. 

With all aquariums, it is important to choose the right sized heater that is not only powerful enough but fits properly in the tank. This is even more important when dealing with nano tanks. 

Smaller tanks will mean smaller sized equipment. The Nuvo Fusion 20 has a chamber in the rear filter section that will fit a heater. You have the option of mounting a heater inside the display area, but most people will fit it in the back where it is hidden away from view and you won’t have to worry about livestock being around it. 

The rear section of this tank has a baffle height of 7.9”-9.8” so you don’t really want a heater that is taller than that. I find that an 8” heater will work perfectly in the Nuvo Fusion 20. 

A good guide to follow is to choose a heater that is a minimum of 3.5-5 watts per gallon. So a 75 watt to 100-watt heater is sufficient for a 20-gallon tank.

The following heaters are all rated for 20 gallons or more and will fit properly in the rear chamber of the Nuvo 20.

If you are looking to purchase a Nuvo Fusion 20 aquarium kit, check out today’s price on Marine Depot here.


nuvo fusion 20

Cobalt Neo Therm 75 watt

The Cobalt Neo Therm heater is the most popular choice for the Nuvo Fusion 20. It is rated for a 20-gallon tank and is 7.75” tall.

This heater is unique as it has a flat and modern design. It is fully submersible and designed to be energy efficient and durable. Its shatterproof design will ensure safety and is guaranteed to last. 

Features and specs:

  • Can be placed forwards or back with the included reversible holder.
  • The One-touch system is accurate within +/- 0.5 degrees.
  • LED display
  • Thermal protection circuitry prevents overheating.
  • Shatterproof outer casing.
  • Rated to raise temperature 2-3 degrees F above ambient temperature. 
  • 3 Year warranty


  • Reliable
  • Shatterproof
  • Flat design


  • Included suction cups are not great

The Cobalt Neo Therm 75 watt heater is available on Amazon here. 


Marine Depot Aquarium Supplies

Eheim Jager 75 watt

Another great heater choice is the Eheim Jager 75 watt. These heaters have been around a while and are proven to work. They are trusted by many and are my personal favorite heater for all tank sizes. 

These heaters are known to be large in size and the 75 watt is the only one that will fit in the rear chamber of the Nuvo Fusion 20. Larger sizes will fit in the display only. 

The Eheim Jager heaters are fully submersible and are designed with shatterproof glass. They are built free of any pollutants and are resistant to any substances. 

They can withstand any extreme heat fluctuations and ensure even heat distribution throughout the heater. 

Features and specs:

  • Thermo safety control will shut off automatically if dry.
  • TruTemp dial will recalibrate the heater for precision.
  • Shock and shatterproof glass.
  • Bright On/Off indicator.
  • Control temperatures between 65F and 93F with +/- 0.5-degree accuracy. 
  • Rated for up to 30-gallon tanks.
  • Includes mounting bracket and suction cups. 


  • Reliable and durable
  • Thermo safety control
  • Shatterproof
  • Long power cord (5.6 feet)


  • The dial can be difficult to turn over time

The Eheim Jager 75 watt heater is available on Amazon here. 


Hydor 100 watt

The Hydor 100 watt heater is another great choice for the Nuvo Fusion 20. The heater is 8.9” tall so it would be the tallest size to fit into the rear chamber of the tank. The Hydor heater is fully submersible and shatterproof with high resistance to heat. 

Features and specs:


  • Rated for up to 26 gallons
  • Shatterproof glass
  • Shock resistant
  • Safety shutoff in case of running dry – uses PTC technology
  • Precise temperature setting
  • Includes mounting bracket and suction cups


  • Affordable and energy-efficient
  • Longer power cord – 73 inches
  • Reliable and precise 
  • 2 Year warranty


  • Complaints of the heater being clunky for small tanks
  • Suction cups not great but do the job

The Hydor 100 Watt heater is available on Amazon here.

Do you need a heater for the Nuvo Fusion 20?

Yes, all saltwater fish require a certain temperature to stay healthy. Many fish are sensitive to temperature changes and you should maintain a constant temperature at all times. Although there may be a range of temperatures that are safe for specific fish, it’s more important to keep the temperature constant than fluctuating within that range. A good quality heater will keep the water temperature in your tank at the desired level usually within +/- 0.5 degrees. 


Can a fish get burned by a heater?

Yes, it is possible for a fish to be burned from a heater. Usually, this happens when they get trapped in between the heater and the glass. With the Nuvo Fusion 20 aquarium, you have the advantage of putting the heater in the rear filtration section and avoiding your fish interacting with a heater in the tank. 


Do you need a heater controller?

I always recommend that you add a heater controller to your must-have list. The Inkbird temperature controller is one of the best purchases you can make in the aquarium hobby. It will control your temperature and shut the heater off in the event of a heater malfunction causing it to stick in the on position. The Inkbird is not expensive and worth their weight in gold. I won’t have a tank without one. They are available on Amazon here. 



Choosing a heater that is properly matched for your tank is very important. Although the heaters mentioned here will fit in the rear filter chamber, you also have the option of using a larger heater inside the tank. A small heater of this size is affordable and easy to buy so if you need to replace them it won’t break the bank.