Moreys actually may hold the record for being the oldest saltwater fish kept in captivity, as they were actually kept over 2,000 years ago in specially built pools in ancient Rome.
In a tank that large, you could probably end up with a nice display by picking a tankmate (if you want any at all) by picking a mid to topwater fish such as a volitans as a tankmate.
Many people don't think to consider what part of the tank is most used by what fish in selecting their specimens and by "layering" your fish you can get maximum use with a minimum of conflict, even among somewhat aggressive species.