Hello! As some of you may have heard I had plans to do a monster 500g. But due to $ I would be able to cut the price down in half by going with a 325. For the 500g I was going to go with 2-3 motoros. But I'm worried about size. What stingrays can live with discus (and maybe an arowana, still working that out) in a 325? Would the arowana eat a teacup? The dimensions are 120x30x24. Thanks!