The rabbitfish (monster) and pacific sailfin were the first two fish in the tank. They came in together and were both about an inch long (~3 years ago).
The Red Sea purple tang came in (~4") with a large naso tang (7") next. The naso was the boss. This was excellent since he had a mild temperment and enforced hierarchy without violence. Size was enough.
I then added 6 small yellow tangs (1.5") at once. This introduced ich (I was buying from LA... Didn't think I needed to quarantine). The naso thrived for a while but got ill and died in 24hrs unexplainably. That left the purple as the boss. She was violent to the yellows who were equally violent to each other. In the end, they settled into an acceptable order except for the smallest runt that they executed.
The purple in charge was hell. No new fish could be added as long as she was boss. So, I needed another large but mild fish. These are hard to find. Tried several but none were big enough.
Then I bought the large hippo (8") from a reefer who was exiting the hobby. Came with the mandarin, inverts and coral, etc... It was a near full tank transfusion. But the intent was to add a large but mild mannered boss to keep the purple in check. I was still missing my naso (I loved that fish like a real personal pet).
The hippo was so much bigger, but also so much milder than the purple. It hid a lot, but would be dominant when out. That did temper the purple, but not enough to allow me to add new fish. It was good to keep her from going aggressive bananas though.
During that time, the purple grew very slowly while the yellows, rabbit and pacific sailfin grew like crazy! They were all about 3-5" together when I saw this gorgeous Red Sea sailfin. Man! The personality, the grace, the beauty... It was like a work of art on the canvas of marine life. It was about 5"-6" but those sails made it stand out in physical stature. It could be a mean boss though... There's that aggressive streak in behavior. I took the risk and immediately, all four were in play: the rabbit, pacific sailfin, purple and Red Sea sailfin. The hippo only came out so they all knew he was still bigger but no physical engagements or threats to or from.
The sailfin took on the purple and its sails definitely worked. The smaller sailfin went after it hard, but there was at least an inch difference and it couldn't keep up. The rabbit though did.. Establish a weird trio in second place - Red Sea sailfin, purple and rabbit.. With the pacific sailfin and then largest yellow in third and fourth place. The hippo was the usually absent #1.
A year later, the hippo is much better adjusted and feeds off the nori in the front daily, forcing it to take a more active social role. Unfortunately, the most "truly" dominant fish is the rabbitfish. It's now a monstrous 8" on its own and very fat. It is the most aggressive and while the hippo still has the respect of all, it's the rabbit that runs the show. Followed by the Red Sea sailfin and then purple. Then the pacific sailfin and 5 yellows.
I recently added the copperband and the purple took an instant dislike to it. Dislike? More like murderous intent. Along with the canal of her 5 smaller yellow cronies, they were going to kill it. Thankfully, my rockwork has a maze of circular paths to swim around and hide, but still 6 against 1 is bad odds.
I put a large mirror on the front glass and everyone immediately had bigger problems. The rabbitfish took it hardest. (The male anthias too, but that's a separate hierarchy). But that distracted everyone from the CBB who was able to feed and sleep in safety for a couple of days.
It's settled in just above the lowest yellow... But things are still in play.
The mirror also seems to have shaken up the top roles- hippo, rabbit, Red Sea sail, purple, pac sail, and top yellow...
And this is where my wife said "enough"... They're not getting along. I think it's a matter of time and attention.
