Heaters
Automatic submersible heaters with thermostat, nano heaters and inline heaters for external filters.
Advice and care
How to choose an aquarium heater
Wattage and type depend on the tank's volume and whether you run an external filter.
Wattage
The maker gives the right volume for each model – choose by that.
Inline
An inline heater on the external filter hose is invisible in the tank.
Placement
Put a submersible heater where the flow is good so heat spreads evenly.
Popular brands
All brandsFrequently asked questions
What temperature is right for an aquarium?
Most tropical fish and plants do well at 24–26 °C. Some species, such as goldfish, prefer cooler water.
What happens if a heater is out of the water?
A heater left on out of the water can overheat and break. Switch it off before a water change.
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A heater keeps the water at a temperature suitable for tropical fish and plants and prevents sudden swings at night and in the cold season. The thermostat measures the water temperature and switches heating on when needed, so no manual adjustment is needed.
The range includes submersible heaters with an electronic thermostat, a heater with day and night modes, a small heater for nano tanks and inline heaters for an external filter hose, one of them controlled via Bluetooth. A submersible heater is easy to install, while an inline heater takes up no space in the tank.
If the room is cool or the aquarium stands near a window, choose a heater whose volume range goes beyond your tank size. In a large tank, two smaller heaters spread warmth more evenly than one. Before a water change, switch the heater off and let it cool for a few minutes.
Related guides
All guides
Heater7 min read6 sections
Aquarium heater: wattage, placement and temperature
How much heater wattage a tank needs, how glass, in-line and filter heaters differ, where to place the heater and how to keep an eye on the temperature.
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Beginners2 min read5 sections
How to start an aquarium: what to buy and how to set it up
A step-by-step guide for beginners: choosing a tank, the equipment you need, substrate, plants, and cycling the aquarium before adding fish.
Read the guide