Display Refugium Planning

Hello everybody, I need some opinions here. I am planning on adding a 55 gallon tank to my current 110 gallon display as a display refugium. What i need help with is deciding whether to add the 55 straight to my existing system and add macroalgae as i go or if i should run the 55 independently first and add it after if has cycled itself. If i add it directly i would use dry sand and dry rock and just let my existing bacteria colonize it. If ran seperately i would use live sand and live rock