hygger Betta Fish Tank Heater

2 customer reviews
5.00 out of 5 based on 2 customer ratings


Submersible aquarium betta water heater with memory function and over-heat protection.

Package includes:
1 x Smart PTC heating rod with sleeve
2 x Suction cup
1 x IC temp controller
1 x User manual

  Get Coupons

Get Petnanny Store Discount Code: Hygger 10OFF


This fully submersible water heater enables memory function and over-heat protection. Automatically shut off when it overheats, and resets when it cools down.

Made with premium titanium and double sealed by a black protective guard, this 500W heater is resistant to explosion and corrosion and protects betta fish and other live stocks from punching and scalding.

Rapid heating rate

The heating rod is made of semiconductor ceramic material, heating water fast.

Built-in external IC temp controller

The built-in external IC temp controller makes it easy to read the LED digital number that shows real-time water temperature. Temp accuracy is ± 1 °F.

Built-in hand button

With the built-in hand button, you can set the betta fish water temp without getting your hands wet. Keep pushing the button will cycle through all the set temperatures. Big fish tank temperature can be precisely adjusted from 70 to 94 °F.

Dual relay design & ABS protective sleeve

One heater with two relays is like one person with two hearts. It is safe for fish tanks from 60 gallons to 180 gallons. ABS protective sleeve prevents small fish from being harmed. This hygger betta fish tank heater is suitable for freshwater only.

Over-heating protection & Anti-exposing protection

When the water temp passes 97 °F accidentally, the water heater will stop heating automatically. When the water temp is lower than 93 °F, the heater will start working automatically.

When the heating rod is exposed to air, the heater will shut off automatically. When the heating rod is completely immersed in water, it will start working automatically.

Directions for Use

Step 1: Place the water heater as shown below.
water heater
Step 2: Plug in and the IC temperature controller will display the present temperature.
Step 3: Press the “Set” button until it reaches the temperature you desire. Then the display will flash the desired temperature value 3 times and display the current water temperature after that.
Step 4: The settings are done. You can press the “Set” button persistently to display 70-94 °F in a cycle.

4 Digital Display Models

1. heating waterWorking: The heater is heating water.
2. fault codeMalfunction: It will show the fault code
3. ThermostaticThermostatic: The water temperature reaches the desired value.
4. fault codeOut of Water: The heating rod is out of the water and shows fault code “Er”. The heater will stop heating.

Error Code Explanations and Solutions

Er: The heating rod is exposed to the air. Place the heating rod fully in water.
EH: The water temp is higher than 97 °F. Cool the water to a normal temperature.
EC: Communication failure. Discard heater.
E3: The relay is melted. Discard heater.
H1: The temperature sensor is in short-circuit protection. Discard heater.


hygger 921 heater parameter

Additional information


500W, 800W

2 reviews for hygger Betta Fish Tank Heater

  1. Charles Stankus

    This heater has been amazing,best one i ever owned.I had mine for about 4 years.I have a 200 gallon African cichlid tank,from the day I bought it,I set it to 79 degrees and walked away,up until today received an E3 code,tried to find a fix,nope relay melted.But I will own another that’s for sure.But besides the relay,well built guys.

  2. Paul

    Love it makes life easy in the tank great value

Add a review

Your email address will not be published. Required fields are marked *