hygger Small Aquarium Betta Heater with Digital Display
A thumb-size quartz heater with an external digital controller.
- 10W and 25W sizes (series to 100W)
- 59-93°F range (10W)
- 4.1" (10.5cm) long
- LED display, external controller
- Dry run and over 95°F cutoff
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Pros
- Very small body
- Live temperature readout
- Error codes for faults
Cons
- Controller cable to manage
- Small wattages only suit small tanks
At a glance
A thumb-size quartz heater with an external digital controller.
A tiny, adjustable heater with real safety features for nano and betta tanks.
- 10W and 25W sizes (series to 100W)
- 59-93°F range (10W)
- 4.1" (10.5cm) long
- LED display, external controller
- Dry run and over 95°F cutoff
Product Specifications
- Brand
- hygger
- Model
- HG-031
- Color
- Black
- Size
- 10W, 25W
- Dimensions
- 1.2 x 1.2 x 4.14 inches
- In the box
- 1
The hygger Small Aquarium Betta Heater (model HG-031) is a mini submersible heater with an LED digital display and an external temperature controller. The series comes in 10W, 25W, 50W and 100W for tanks up to 5, 10, 16 and 26 gallons respectively. This page covers the 10W and 25W sizes.
Thumb size
The heater body is only 4.13 (10.5cm) long. In a nano or betta tank, a full-size heater takes up a lot of space and is hard to hide. This one tucks behind a plant or into a back corner.
Range and control

The 10W version has a temperature range of 59-93°F and suits tanks of 1 to 5 gallons, fresh or marine, glass or acrylic. It also works in small turtle tanks. The controller sits outside the tank with an LED display showing water temperature in real time, so you can adjust settings without wet hands.
Protection

The heater is made of 2mm thickened quartz glass to resist breakage and corrosion. If water temperature exceeds 95°F, or the water level drops below the minimum line, the heater stops and the controller shows an error code: HH for high temperature and E1 for out of water.
Choosing a size

- 10W: up to 5 gallons
- 25W: up to 10 gallons
- 50W and 100W: larger sizes up to 16 and 26 gallons
In a cold room, step up one size.
Safe use
Unplug the heater before cleaning the tank or changing water. Place it where filter flow passes over it to spread heat evenly.
Compare
For a preset heater with no controls at all, see the PULACO 25W mini heater. For larger tanks, the hygger 100W heater is a bigger option from the same brand.
Who it suits
Betta and nano keepers who want adjustable temperature, a live readout and safety cutoffs in a very small heater.
The Bottom Line
A tiny, adjustable heater with real safety features for nano and betta tanks.
View on Amazon →As an Amazon Associate, AquaticRig earns from qualifying purchases.
Frequently Asked Questions
What tank size is the 10W for?
1 to 5 gallons.
What do the error codes mean?
HH is high temperature and E1 is out of water.
Is it saltwater safe?
Yes, for fresh and marine water.



