I have a 29 gal with a 10 gal sump ,and plan to upgrade to a 75 with a 30 sump. Here is what I plan to do. First fill the 75 completely, add new sandbed, and let the system run for about a week. Then once Ca,Alk,pH, Salinity ,ect are all up to par I'll place corals ,rock ,fish in a trash can...