PLEASE HELP ME! my silver arowana has been eating less and less over the course of the past 3 days. this afternoon, he ate one pellet, and ignored the rest. I tested the water a week ago, it was fine, the only thing wrong with him is that he is not eating, and doesnt come over eagerly like he normally does to feed. he is not sitting on the bottom or anything like that. he is alone in a 220 gallon tank, and is about 20 inches long. PLEASE HELP ME THIS FISH IS EVERYTHING TO ME!!!!!!!!!!! Also tried silversides, didnt touch them.