Thanks to @Biota_Marine I just acclimated and add 5 new captive-bred fish to my reef! A group (3) of Court Jester Gobies (Koumansetta rainfordi), a Lyretail Damselfish (Neopomacentrus azysron), and a Blue Mandarin Dragonet (Synchiropus splendidus). I haven't seen much aggression between fish in my tank except between my yellow tang and yellow watchman goby but I'm always prepared for some territorial aggression. What I did not expect this time around was for my yellow tang to be a fish referee. Has anyone else experienced this before? My royal gramma has been the only aggressor since I added these group of newbies and to my surprise as soon as my tang noticed this she immediately began putting herself in between my gramma and the new fish. She doesn't seem to be asserting her dominance on the gramma but literally seems like she is trying to mediate the aggression. I will post a video of it if I can catch them interacting like this again.