my jack dempsey wont eat!

my poor jack is just barely eating. when i first got him all he ate was
goldfish, i got him on carnivore pellets, wich at first he ate
ravenously, then he all of a sudden just stopped! I thought he might
perk up if i gave him a few goldfish and he ate just a few of them then
wouldnt touch them for 2 weeks so i took them out. I tried beefheart and
he refuses that too.he also seems to get kind of goldish fuzzy looking
when stressed, but this sort of disappears if he gets angry, like when
he chases the goldfish, is this normal? other than looking thin,he
doesnt seem to lethargig, he spends a lot of time re-arranging things in
his tank, also he has started bumping into me when i put things
right.Any suggestions? Thx.