My firefish hides most of the time and only comes out to feed. Sometimes I won't see him for a couple of days, and I've feared he was dead. But he always shows up eventually. He wasn't always this way, but I think my 6 Line has begun bullying him.
As for the 6 Line, he is always active, swimming in and out of the crevices in my rocks. But he's still a juvenile, and I know he may become a problem at some point. I hope not, as he's one of my favorites to watch.
My Royal Gramma is pretty active too. He hangs out in a cave some, but he's usually swimming about or poking into any hole he can fit into.
Along with my clowns, my blue chromis is always out and about. My bangai too, but as noted, they don't do much. As for being nocturnal, I always find mine nestled into a hole in the middle of the night.