Hardware Setup - Extended GRO
If you want to extend your basic CityOS GRO device you can play around with other sensors such as water level sensor, real time clock or relay.
Water Level Sensor
If you want to add more sensors to your basic GRO device you can start with liquid water level sensor - a device used to detect the level of liquid within a tank.
DS3231 Real Time Clock
Next we can add DS3231 real time clock (abbreviated as RTC) so we will be able to read Unix time.
Relay module can be used to control various appliances and equipment with large current. This module is perfect for controlling external devices like pumps, lights etc.
This is more elegant version, and will be easy to set up since you have already learned how each sensor work.