At this time, there is not a dark mode or option to control the blue light while still running the fan on Air Pro. The single, integrated PECO-Filter used in Air Pro, Air Mini and Mini+ have been designed to minimize the amount of visible blue light from the device.
Please keep in mind that all Molekule devices use PECO technology, which uses low-energy ultraviolet (UV-A) light to initiate the catalytic reaction that destroys pollutants. This blue light is necessary for the design and effectiveness of PECO technology.