If you are looking for a tankmate and have a local fish store that can order you an adult black shark (Labeo chrysophekadion), makes a great tankmate for a dovi. Ive got one with a red devil and a jag both 11 inches, the shark is 15 inches and he the dominant fish These guys potentially can reach 24 inches in length and are very tough fish http://www.aquahobby.com/gallery/e_morulius.php