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Cobalt Aquatics Neo-Therm Submersible Aquarium Water Heater

$59.95 - $134.95
(2 reviews) Write a Review

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Submersible Water Aquarium Heater

When you’re installing your Cobalt Aquatics underwater heater, the ultra-flat design makes it simple to hide nearly anywhere in your tank. Some of its best features include:

  • Shatterproof Outer Casing for Extra Protection
  • Microprocessor-Controlled Thermostat for Better Accuracy
  • One-Touch Setting & Adjustment
  • Simultaneous Displays of Set & Current Temperature
  • Easy to Read Multi-Color LED Screen
  • Removable Suction Cup Mounting Bracket for Quick Installation

It can maintain the temperature of your water to within ±0.5 degrees Fahrenheit! This aquarium water heater has a range between 66-96 degrees Fahrenheit today.

Extra Safety Features

You want a safe aquascape for all your fish and plants, and the Cobalt underwater heater delivers it. It comes with thermal protection circuitry that automatically cuts power to prevent any damage from overheating. There is also an audible alarm that sounds in case the tank temperature gets too high. If it exceeds your set temperature, you’ll know it!

Power Maximum Aquarium Size Size
50 W 4 - 10 Gallons 6.5" x 2" x 1"
100 W 16 - 24 Gallons 9.75" x 2" x 1"
150 W Up to 40 Gallons 10.88" x 2" x 1"
200 W Up to 55 Gallons 10.88" x 2" x 1"
300 W Up to 300 Gallons 10.88" x 2.13" x 0.8"


Swap out your current aquarium water heater with a more effective, efficient product. Order your own Cobalt heater and get free shipping!

Reviews (2)

  • 5
    Most Consistent Heater

    Posted by Brittany B on 30 Apr 2020

    My reef tank has never been at a more consistent temp than with this heater. I had read a lot of reviews but I’ve had this heater for about 2 weeks not and my temp has even fluctuated a degree. Consistent 79.2. I run a 13.5gal and the 75watt is perfect.

  • 5
    Cobalt Neotherm Heater

    Posted by Suzan Garau on 15 Jan 2020

    I have become a huge fan of this new aquarium heater and have replaced all my others. I have lost fish when the glass tube heaters inevitably fail and overheat or stop working. These keep my tanks at a steady temperature, and their slim flat shape and black color look great in the tank. Modern Aquarium got my order to me quickly and safely.