240 gallon tank. Currently 3 tangs and 3 clowns (2 black & white, 1 normal). The 2 B&W are pretty big. I would say full grown if not real close, and the orange is a good bit smaller. Not sure how long the three have been together because I bought the tank setup with fish. Anyhow all stay in the top back corner next to the overflow. They venture out to about mid tank back wall to eat, but otherwise never leave this post. The orange will venture off on his own to the other side sometimes, but always goes back. What is up with this behavior? They did this in this tank before the move, and did this in a buddies tank that he had setup to hold my fish in while I got this tank set back up. They pick a top corner of the tank and just stay there.... It's honestly like they aren't even in the tank most of the time.