Eheim Thermocontrol heater — the precision Jäger with a thermostat dial

The Eheim Thermocontrol is a precision submersible aquarium heater with an adjustable thermostat dial, available from 50 W to 300 W for freshwater and saltwater tanks.

This is Eheim's legendary heater — known in North America as the Jäger TruTemp (the name used across the official distribution network). Per the technical sheet published by Eheim, the Thermocontrol regulates with ±0.5 °C accuracy over an 18 to 34 °C range, and its dial can be recalibrated by up to ±2 °C to match your reference thermometer.

Features according to the manufacturer

Control accuracy: ±0.5 °C — temperature range 18 to 34 °C (64 to 93 °F)
Dial recalibration up to ±2 °C
Laboratory glass jacket with thermal shield effect — widens the exchange surface and protects fish from direct contact
Fully submersible and watertight
Automatic dry-run shutoff (Thermo Safety Control)
Heating indicator lamp
Double suction cup holder included · cable approximately 170 cm (5.6 ft)
Freshwater and marine · 3-year manufacturer guarantee · made in Germany

Eheim publishes the recommended tank volume on each wattage's product page — for example, the Thermocontrol 150 W covers roughly 200 to 300 L (53 to 79 US gal). Write to us with your tank volume if you're hesitating between two wattages.

Why buy at ReefSolution

Delivery across Canada or in-store pickup in Laval. The other Eheim heaters in our catalog:

Eheim Thermocontrol e — the electronically controlled version
Eheim Thermocontrol+ e Wi-Fi — the connected version, controlled from your phone
Eheim Classic 150 external filter — to round out a freshwater setup

Frequently asked questions

What is the difference between the Thermocontrol and the Thermocontrol e?

The Thermocontrol (Jäger) is set with a recalibratable mechanical dial; the Thermocontrol e has electronic regulation. Both are rated ±0.5 °C accuracy per Eheim.