Eheim Thermocontrol Aquarium Heater – 50W, 100W, 150W, 200W & 300W
The Eheim Thermocontrol Heater is a premium adjustable aquarium heater designed to provide accurate, stable temperature control in both freshwater and marine aquariums. Made in Germany and built from temperature and shock-resistant laboratory glass, the Thermocontrol range combines precise heating with dependable safety features for long-term aquarium use.
Temperature can be precisely adjusted from 18–34°C, with temperature control accuracy of approximately ±0.5°C and the ability to recalibrate by ±2°C when required. An indicator light shows when the heater is actively heating, while Eheim's Thermo Safety Control provides automatic dry-running protection.
Available in 50W, 100W, 150W, 200W and 300W variants, making it easy to select the correct Eheim heater for anything from smaller tropical aquariums through to large freshwater and marine systems.
Available Sizes & Aquarium Recommendations
| Model |
Recommended Aquarium Size |
Heater Length |
Diameter |
| 50W |
25–60L |
243mm |
36mm |
| 100W |
100–150L |
319mm |
36mm |
| 150W |
200–300L |
345mm |
36mm |
| 200W |
300–400L |
406mm |
36mm |
| 300W |
600–1000L |
506mm |
36mm |
These are Eheim's manufacturer-rated aquarium sizes and dimensions for the Thermocontrol range.
Key Features
✔ Adjustable Temperature: Precisely set between 18–34°C
✔ Accurate Control: Temperature regulation accuracy of approximately ±0.5°C
✔ Recalibratable: Temperature setting can be adjusted by up to ±2°C if required
✔ Fully Submersible: Watertight construction allows complete submersion
✔ Thermo Safety Control: Automatic dry-running shut-off for additional protection
✔ Laboratory Glass Construction: Temperature and shock-resistant glass designed for aquarium use
✔ Even Heat Distribution: Glass jacket increases the heating surface for consistent heat transfer
✔ Heating Indicator Light: Clearly shows when the heater is operating
✔ Fresh & Saltwater Suitable: Designed for both freshwater and marine aquariums
✔ Secure Mounting: Includes a double suction cup holder
✔ Approx. 170cm Power Cable: Provides flexibility when positioning the heater
✔ Made in Germany
✔ 3-Year Manufacturer Warranty
Choosing the Right Eheim Thermocontrol Heater
50W – 25–60L
Ideal for smaller tropical and marine aquariums where reliable adjustable heating is required.
100W – 100–150L
Designed for medium-sized aquariums requiring greater heating capacity.
150W – 200–300L
Suitable for larger community, planted, cichlid and marine aquarium systems.
200W – 300–400L
A strong option for larger aquariums requiring consistent temperature control.
300W – 600–1000L
The largest option in this listing, designed for very large freshwater and marine aquarium systems.
Perfect For
✔ Tropical freshwater aquariums
✔ Planted aquariums
✔ Community fish tanks
✔ Cichlid aquariums
✔ Large display aquariums
✔ Marine and saltwater aquariums
✔ Aquariums requiring precise adjustable temperature control
Important Heater Sizing Information
The aquarium volumes above are Eheim's official recommendations. Actual heating requirements can vary depending on room temperature, aquarium dimensions, desired water temperature, lid or open-top design, and surrounding environmental conditions.
