Nemo Light - Controller
The Nemo light sensor controller is an optional extra with any of the Nemo Light series.
The controller allows you to use the moonlight mode and thunder storm mode built in. You are also able to dim down the brighness of each channel (blues or whites) to whatever suits your aquarium best.
you can then allow the light sensor to detect either when the lights in the room go off or the sun sets the lights on your tank will automatically change for you.