OK I was getting some feeders for my puffer, and saw this little brown knife, and he was just hovering at the top of the tank. He looked sooo sad. He was arched a bit, head hanging down and only the first half of his fins seemed to be moving. I already have a BGK, but am debating on getting him. I have the BGK in the 75 growing and I thought about adding this guy to my 150 with my parrots and fronts, and fattening him up. He is only about 3 inches. What do ya'll think?