After your tank is empty, ( you can reuse the sand) soak your tank in vinegar for a while, like overnight. After, the coralline will wipe off and you can rinse the tank out until it’s clean. You can rinse the sand and then boil it, then rinse again afterward. (I just use the hose outside).
What type of filtration do you want to use? And what types of inhabitants do you want to stock?
What do you want to know? Saltwater, I never really can pipe up on, but freshwater I can more.