The integrated 24-hour timer makes it easy to control the three independent channels: Bright white, sparkling blue and color enhancing LEDs for maximum beauty. Each BioCube also includes automatic 30 minute sunrise/sunset and 60 minute moonrise/moonset functions to replicate a natural day/night cycle. BioCubes are a great starter aquarium because they feature a compact and customizable filtration chamber that is already built-in to the back of the aquarium. Among other great features are the quiet submersible pump, dual intakes and adjustable return nozzle. Each aquarium is also 2" taller than the original BioCube aquariums, creating a larger viewing area with the new 16 and 32 sizes. Compatible with all existing BioCube accessories.