I love all of gods creations other than microwaves, but my least favorite fish would have to be bubble eye goldfish. The things must be in excruciating pain...
love all fish
but there are some i would never get. EG a dyed Blood Parrot. love non dyed ones... but dyed ones...just eew. LOL
as far as a natural fish that i like but would never own... maybe Pacu or Moonlight Gouramis.