Why You’ll Love It
hygger submersible aquarium heater is ETL certified, comes with a 2mm thick glass tube, anti-collision, explosion-proof, and corrosion-resistant, dual-purpose for freshwater and saltwater tanks up to 80 gallons. The high-efficiency heating wires have a large area and are arranged tightly to increase the heating area and transfer the heat evenly.

Key Features
ETL Certified for Quality and Safety
The hygger 998 heater features an adjustment knob and is ETL certified, ensuring quality, and can be easily concealed within the aquarium. It includes an internal fuse for safety, which automatically disconnects power if the heater is out of water for more than 3 minutes, preventing damage to the unit.
The aquarium heater will cease operation if the water temperature exceeds 93°F, preventing overheating and ensuring the safety of your aquatic environment.
Note: Even if you re-submerge the heater after this auto-shutoff, the heating indicator will remain on, but the heater will not resume operation until manually reset.

Precise Temperature Control
Rotate left and right to adjust the temperature within a range of 68°F to 93°F, with an accuracy of 2 degrees Fahrenheit. A high-precision temperature sensor can display the temperature difference range to 0.1℉. As a fully submersible heater, it comes with two suction cups for versatile mounting in either horizontal or vertical positions.
Real-time Temperature Monitoring
This heater’s thermometer has a monitoring range of 0°C to 50°C (32°F to 122°F), ensuring accurate real-time temperature monitoring. A long-lasting, replaceable battery powers it. The three-digit digital display provides precise readings to one decimal place, enhancing the accuracy of temperature tracking.


Intuitive Heater with Built-in Thermometer
A built-in temperature probe for robust functionality. When the surrounding water temperature reaches the set temperature, the HG998 heater stops working; It will start to work when the water temp is low, and cycles over and over again to achieve equilibrium.
Durable Quartz Glass Construction
The 998 aquarium heater tube is crafted from heat-resistant quartz glass with a thickness of up to 2mm. It utilizes white alumina sand as a heat-conducting medium for efficient heat distribution. With proper care, the service life can extend to over 3 years.
Usage Tips

User Tips for Safe and Effective Operation:
1. Ensure the aquarium heater is always fully submerged in water to prevent damage and ensure even heating.
2. For optimal circulation, attach the heater horizontally or vertically to the side of the tank near the water intake or along the water flow path.
3. Avoid burying the heating element in sand or stones, as this can insulate the heater and lead to overheating.
4. Keep the temperature controller dry and away from water to prevent electrical issues.
5. Do not connect the power supply until the aquarium securely installs the heater.
6. Allow the heating element to cool down before moving the heater or changing the water to avoid the risk of breaking the glass.
Specification

Package:
1 x Aquarium heater
2 x Sucker
1 x User manual
















All of the Hygger products I have ever used have always worked phenomenally! All I use is Hygger products for all of my aquatic fish keeping needs and will continue to do so. Great job guys!
Does what it says.
Works great, has been in use for months now and has maintained temperature with no fluctuations. The suction cups stay on well also.
Nice heaters! I really appreciate the easy adjustment knob at the top. It really makes adjusting the temp easy and the temperature display is great too. The compact size is nice. They fit vertically in my taller tanks much better compared to other brands. The 4 suction cupped holder holds the heater in place well also!
Side note, the included thermometer reads surprisingly accurate vs a infrared one. I’m not certain how it will do overtime but was a nice additional item.
Excellent product
Sticks very well to tank with 4 suction cups although they are removable if you want to use less. Very accurate to the setting + a bonus thermometer comes with. Very sturdy and overall happy. Have been using it for about a week now no issues.