I never add a single tang because it would be picked on. Water changes are thru the quarantine so they are all ready used to the exact water they will move to. They are next to the tank they will move into so have seen their new tank mates for a while. I rearrange the rocks or add new ones to the tank they will move to and add them after the lights go out. Adding them in groups of at least three has worked well for me. They start in a quarantine 4/2/1 divided into three sections. From there they move to a 6/2/30". Then they grow to the 8/2/30" tank. Not counting quaratine water is 850 gallons tied together, these three are the tanks the tangs will see. This gives all small tangs six feet of swim room and medium eight feet of swim room. I do not consider these tangs grown yet and am working toward my last new tank that will be quite a bit larger than where they are now. That will be the tank that I will then work more with corals than what I have now and want to add clams. On the fence now since the size of the new tank will make it acrylic if it will have sand or not.