Doesn't it seem like there's some problem or other with any fish you keep? Here's the list of problems I've encountered with different reef fish and how I rate them on a scale of 1 to 10;
Damsels: They're aggressive little monsters who harass other fish endlessly. (my vote; 0)
Clowns: they bite when you put your hand in the tank. (I've discovered a solution to this; I wear tank gloves whenever I put my hands in the tank - for about 6 weeks. The clowns learn that biting doesn't work, and they stop trying). (my vote; 8)
Anthias: they need a constant supply of micro life (copepods, etc) to thrive. So, they only do well in mature systems. (mv; 8)
Wrasses: they're hyper little boogers and they eat or harass shrimp. (at least some of them do). They also hide out a lot, so you don't get to watch them. (mv; 7)
Tangs: they poop massive amounts and then eat it. Ewwww. And, you have to feed them several times a day, so they can poop even more. (mv; 7)
Butterfly fish: not reef safe. (mv; 5)
Angels: not reef safe. (mv; 2)
Mandarins: specialized diets and they die after a few months from starvation.
(mv; 0)
Gobys: Some of them hide out and disturb the SB, but mostly they're pretty good reef fish. (mv; 7)
Blennys: Great fish, but they peck at corals. (mv;8)
That's about it for fish I've had; What your vote for various fish?