My mbu is sick! he's about 12" and had him for a 15mths and a week ago i totally rearranged the tank and since then he's been sulking and not eating and then tonight i found him on the surface partly puffed up and on his side. the water parameters are absolutely fine and i assumed he was just sulking as mbu's can do but now i very much fear the worst. anyone got a clue what i can do?!?!