Gosh, after listing these out, I realize that a) I've had a lot of fish, and 2) I'm glad this is only a saltwater list. :0) To be clear, I don't necessarily "hate" any of these fish, just would not buy them again.
Tomato clown with a bullet! These things are absolute terrors!
Domino damsel - unless it was in a tank with triggers, eels, etc. They are SO cool looking but just such little a$$holes. This is also true for 3 stripe, 4 stripe damsels. I do have some very nice Talbotts, azures, and half blacks now FYI.
Undulated triggerfish - looks amazing but is pure evil. But I love triggers otherwise. My humu is terrific.
Lionfish - now that they are invasive in the Atlantic/Caribbean I just can't look at them the same as I did as a teenager. Just want them all dead. :0)
Squirrelfish - their mouths are much bigger than you think and so are their appetites.
Grunt - same as above, but less colorful. Was a fun fish, but not one I'll buy again.
Hamlet - very cool fish but never had any luck with them doing well. Done trying.
Fimbriated Moray - truly an eye-catching fish. Voracious appetite and highly irritable. Wasn't able to keep it with anything else. Would go with Moray again but a more "docile" variety... which is almost any other species. :0)
Butterfly (any) - I just don't trust them. Raccoon butterfly caused the demise of a 100 gallon system many moons ago. I can't forgive the Family.
Panther grouper - I won't buy ANY grouper anymore unless it's cooked. Just not a smart purchase for the vast majority of aquarists.
