I have a royal knife- I saw the specimen they had in the big tank (well over 2 foot) and had to have one- the one I could afford is about 12". Problem is I have had him for around 2 months but he barely seems to eat anything. He is in with mainly cichlids but seems very shy, I feed a lot of bloodworm etc but he never seems to get interested in it and is getting pretty thin now- any ideas?