I currently have 3 radion xr30 G3 over my tank.
Thinking about replacing the 2 other ones with xr15 G4 pro.
Or another option is replacing them with xr30 g4
What are your criterion for an "upgrade?" The new lights will be different, but they might not be an "upgrade?" What don't you like about what you have and what are you looking for with the new lights?
