Welcome to the third guide in reef-pi series.

See the second part of this series here

In this guide, we'll be building a temperature controller using reef-pi. Corals are sensitive to temperature fluctuations and only survive in specific temperature. Higher order animals, such as marine fish can withstand much higher temperature fluctuations than coral. Tropical corals thrive at 78 degrees Fahrenheit. In reef aquariums, submersible heaters are used to keep the tank temperature at 78 degrees. For places where the indoor temperature gets really hot, chillers are used to cool down the aquarium water temperature to the desired level. A temperature controller automates heater and chiller on/off by sensing aquarium temperature, in turn maintaining a stable aquarium temperature.

Heaters are also prone to failures. Heater failure is one of the most common causes of tank crash (loss of all tank inhabitants). Temperature controllers can shut down heaters and alert users when aquarium temperature goes outside a range, providing an extra layer of safety net.

This guide assumes you have a working reef-pi installation with power controller module enabled.