Introduction
This manual provides detailed instructions for the safe and effective use of your hygger Aquarium Heater HG079. Please read this manual thoroughly before installation and operation to ensure proper function and longevity of the product, and to maintain the health of your aquatic environment.

Image: The hygger Aquarium Heater HG079, showing the submersible heating element and the external digital temperature controller connected by a cable.
Safety Instructions
Adherence to these safety guidelines is crucial to prevent electric shock, injury, or damage to the product and your aquarium inhabitants.
- Always unplug the heater from the power outlet before performing any maintenance, water changes, or handling the heater.
- Ensure the heater is fully submerged in water before plugging it in. Operating the heater out of water can cause damage and poses a fire hazard. The heater features an automatic dry-running protection system, but manual prevention is always recommended.
- Do not operate the heater if the cord or plug is damaged.
- This appliance is intended for indoor use only, within an aquarium environment.
- Keep the controller dry and away from water splashes.
- The heater is designed with an explosion-proof quartz glass and a protective guard to prevent burns to fish. However, avoid direct contact with the heating element when it is active.
- Ensure the power outlet has a ground fault circuit interrupter (GFCI) for added safety.
- Do not attempt to repair or modify the heater. Refer all servicing to qualified personnel.
Package Contents
Verify that all items are present in the package:
- hygger Aquarium Heater HG079 (Heating element with integrated sensor)
- External Digital Temperature Controller
- Three Suction Cups
- Controller Bracket
- Hook for Controller
- User Manual (This document)
Product Overview
The hygger Aquarium Heater HG079 is designed for precise temperature control in freshwater and saltwater aquariums. It features a durable heating element and an external digital controller for easy temperature adjustment and monitoring.

Image: Overview of the hygger Aquarium Heater HG079 highlighting key features like fast heating, LED digital display, dry running protection, overheating protection, Fahrenheit/Celsius switch, and memory function.
Key Components:
- Heating Element: Made of thickened high-temperature resistant quartz glass with explosion-proof quartz sand and a nickel-chromium alloy heating wire. Encased in a double ABS anti-scald shell.
- Digital Controller: Features a clear LCD display showing current water temperature, set temperature, heating status, and warning indicators.
- Power Cable: Connects the heater to the power outlet.
- Sensor: Integrated within the heating element for accurate water temperature detection.

Image: Diagram illustrating the construction of the hygger Aquarium Heater HG079, showing the double ABS anti-scald shell, explosion-proof quartz sand glass, nickel-chromium alloy heating wire, and strong suction cups.
Setup and Installation
- Unpack and Inspect: Carefully remove all components from the packaging. Inspect the heater and controller for any signs of damage. Do not use if damaged.
- Attach Suction Cups: Securely attach the three suction cups to the heating element.
- Position Heater: Place the heating element fully submerged in your aquarium. Ensure it is positioned horizontally or vertically in an area with good water circulation to ensure even heat distribution. Avoid placing it directly in the substrate.
- Mount Controller: Use the provided controller bracket and hook to mount the digital controller outside the aquarium. The controller should be placed in a dry location, easily accessible for viewing and adjustment.
- Connect to Power: Once the heater is fully submerged and the controller is mounted, plug the heater's power cord into a suitable electrical outlet with a GFCI.

Image: Visual guide showing how to attach the sticky hook to the tank and hang the controller on the hook for easy access.
Operating Instructions
Understanding the Digital Controller:

Image: Detailed view of the hygger Aquarium Heater HG079 digital controller, labeling the set temperature, current water temperature, working status indicator, danger warnings (probe fault, Hi, Low, Auto shut off), and the temperature set button.
- Set Temp: Displays your desired water temperature.
- Current Temp: Displays the actual water temperature in the aquarium.
- Working Indicator Light: Flashes when heating, remains steady when maintaining temperature or stopped.
- Warning Indicators:
- Auto Shut Off: Indicates the heater has automatically shut off due to being out of water (L1 error).
- Low: Indicates water temperature is below 59°F (LL error).
- Hi: Indicates water temperature exceeds 93°F (HH error).
- Probe Fault: Indicates a sensor malfunction (EE error).
Setting the Temperature:
- Press the "SET" button once. The "Set Temp" display will begin to flash.
- Press the "SET" button repeatedly to cycle through the desired temperature settings. The temperature adjustment range is 59°F to 93°F (15°C to 34°C).
- Stop pressing "SET" when your desired temperature is displayed. The setting will automatically save after a few seconds of inactivity.
Switching Temperature Units (°F/°C):
To switch between Fahrenheit (°F) and Celsius (°C), press and hold the "SET" button for 2-3 seconds until the unit changes on the display.
Memory Function:
The heater is equipped with a memory function. In case of a power outage, the last set temperature will be retained and the heater will resume operation with those settings once power is restored.
Maintenance
- Regular Cleaning: Periodically clean the heating element to prevent algae and mineral buildup, which can reduce efficiency. Always unplug the heater and allow it to cool completely before removing it from the water for cleaning. Use a soft brush or cloth to gently wipe the surface. Do not use harsh chemicals.
- Water Changes: During water changes, ensure the heater remains fully submerged. If the water level drops below the heater, unplug it immediately and allow it to cool before resuming water changes.
- Controller Care: Keep the digital controller clean and dry. Avoid exposing it to direct water spray or submersion.
- Cable Inspection: Regularly inspect the power cord and connections for any signs of wear, cuts, or damage.
Troubleshooting
The controller displays error codes to indicate specific issues:
| Fault Code | Explanation | Solutions |
|---|---|---|
| LL | The tank temperature is lower than 59°F (15°C). The heater will continue heating and sound an alarm. | Allow the heater to continue warming the water. Ensure the heater wattage is appropriate for your tank size. |
| HH | The tank temperature reached 94°F (35°C) or exceeds 93°F. The heater will automatically stop heating and sound an alarm. | Lower the set temperature. Check for external heat sources. Ensure proper water circulation. |
| EE | Probe fault. The temperature sensor is malfunctioning. | Unplug the heater, wait a few minutes, and plug it back in. If the error persists, contact customer support for replacement. |
| L1 | Heater is out of the water (dry burning warning). The heater will automatically shut off and sound an alarm. | Immediately unplug the heater. Allow it to cool. Fully submerge the heater in water before plugging it back in. |

Image: A visual representation of the digital controller displaying error codes (HH, LL, L1) and a table detailing fault codes, explanations, and solutions.
Specifications
| Feature | Description |
|---|---|
| Model | HG079 |
| Power Options | 100W, 200W, 300W, 500W, 800W |
| Voltage/Frequency | AC 110-120V / 60Hz (US Standard) |
| Temperature Control Range | 59°F - 93°F (15°C - 34°C) |
| Temperature Accuracy | ±0.1°F |
| Heater Dimensions (200W) | 11.4 x 2.2 x 1.1 inches (29 x 5.5 x 3 CM) |
| Power Cable Length | 3.9 ft (1.2m) |
| Controller Cable Length | 6.2 ft (1.9m) |
| Material | Explosion-proof Quartz Glass, PC Plastic (Heater Guard) |
| Recommended Tank Size |
|

Image: A table detailing the specifications of the hygger Aquarium Heater HG079, including power, voltage, cord length, temperature range, heater dimensions, and recommended application for various wattages.
Warranty and Support
The hygger Aquarium Heater HG079 comes with a 12-month warranty from the date of purchase. This warranty covers defects in materials and workmanship under normal use.
The warranty does not cover damage resulting from:
- Improper installation or use.
- Accidental damage, misuse, or abuse.
- Unauthorized repairs or modifications.
- Normal wear and tear.
For warranty claims or technical support, please contact hygger customer service. You may be required to provide proof of purchase (invoice/order number) and a description or video of the issue.
For more information, visit the official hygger store: hygger Store on Amazon
Disposal Information
When disposing of this product, please do so in accordance with local environmental regulations. Do not dispose of electrical appliances with general household waste. Seek proper recycling facilities.





