Can I use my existing Radion G5 diffuser on my Radion G6 Yes, the Radion G5 diffuser will absolutely work on the Radion G6! Related articles Radion G5 to G6 Upgrade Instructions How Should I Program My Radion? Can I upgrade my Radion G5 to a Radion G6? Radion G5: How many do I need for my aquarium? Radion G5: Firmware Update in Mobius