Aqqa Submersible Aquarium Heater for Fish Tanks

If you need reliable temperature control in a 115-300 litre aquarium, this aquarium heater provides steady, automatic heating with a visible external LED thermostat controller. The submersible quartz glass element offers fast, even heat transfer while the heat-resistant ABS housing and controller are designed for safe long-term use. Use the heater to prevent temperature swings that stress fish and to stabilise conditions during seasonal or room-temperature changes.

The unit maintains temperature intelligently by restarting when the water drops 1°C below the set point and holds the chosen temperature in 1°C increments across a 15-34°C range. Built-in anti-dry and overheat protection halt heating and display clear error codes – EE for overheating above 35°C and Er if the heater is not fully submerged – so you do not need to guess the problem. The external controller and memory function let you adjust settings without disturbing the tank and keep your chosen temperature after power interruptions. For safe use always fully submerge the heater before switching on, ensure good water circulation, and allow the heater to cool in water for 15-30 minutes after powering off.

Key Features

• Intelligent constant temperature control that restarts automatically when 1°C below the set value, helping to maintain stable tank conditions
• Multiple safety protections with clear LED error alerts for over-temperature and insufficient submersion, reducing risk of damage
• Quartz heating element for fast, even heat transfer and a heat-resistant ABS controller for durable operation
• External LED thermostat controller with 1°C adjustment steps across 15-34°C and a memory function for convenience after power loss
• Suitable for medium to large aquariums around 115-300 litres, offering reliable warming without frequent manual checks

Frequently Asked Questions

Is this heater suitable for my fish tank?

Yes. The 300W heater is designed for tanks of about 115-300 litres and maintains stable warmth suitable for fish within that range.

How do I set and adjust the temperature?

Use the external LED controller: long press the lock button 1-3 seconds to enter settings, then press temperature to change by 1°C between 15°C and 34°C.

What safety protections does it have?

Built-in anti-dry and overheat protections stop heating if problems occur. If water rapidly exceeds 35°C the LED flashes “EE”; if not fully submerged it shows “Er”.

How should I install and use it in my aquarium?

Always fully submerge the quartz glass heater before powering on and ensure good water circulation. After switching off, let it cool in water 15-30 minutes to protect the shell.

Is this heater easy for beginners and what about warranty?

The automatic constant temperature control and memory function make it beginner-friendly. The product comes with a one year warranty for added reassurance.

Check the recent prices for AQQA 300W Aquarium Heater with Thermostat below.