The Inkbird ITC-306 Aquarium Thermostat Controller is an external temperature controller that adds a layer of precision and safety to any aquarium heater. The controller's probe measures water temperature continuously, and the relay cuts or restores power to the connected heater to maintain the programmed set point within ±0.1°C — a level of accuracy that far exceeds most built-in heater thermostats. This precision is critical for caridina shrimp, which are sensitive to temperature fluctuations of even 1–2°C, and for breeding setups where exact temperature triggers spawning behaviour.
The LCD display provides a continuous real-time temperature readout alongside the programmed heating and cooling set points. High and low temperature alarms sound an audible alert if the water temperature drifts outside a user-defined safe range — invaluable for detecting heater failure during periods when the tank is unattended. The controller is compatible with any heater up to 1200 watts, making it a universal upgrade for any aquarium heating setup.
Using the Inkbird thermostat also extends heater lifespan by reducing the on/off cycling frequency compared to the heater's internal thermostat, which often triggers more frequently and with less precision. Hobbyists running expensive breeding programmes or keeping valuable shrimp colonies consider the Inkbird an essential piece of insurance.