I work for a lfs and we recently had a 2.5 ft silver arowana brought in by a customer. He said it was eating dinner shrimp every other week. I fed it some krill and squid day two and that was the last time it accepted food. It's been a month. Nitrates stay low, tankmates are community. He is in a 200gal tank with plenty of room. I have gone so far as to try forcing dinner shrimp in his mouth with a feeding prong. He is starting to look thin and I just don't know what to do about.