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 Can I upgrade my Radion G5 to a Radion G6? Radion G5: How many do I need for my aquarium? How Should I Program My Radion? ESL to Mobius Comprehensive Upgrade Guide