a deep body fish is a fish that is pretty tall and a needle fish in the hobby eat guppies rosy reds and sometimes goldfish and most of those r long an slender so get something built like an oscar or flowerhorn but those r a lil to mean and big so i would probaly suggest even though their not cichlids, either a moray eel or a puffer but a puffer might be a lil mean but those r both brackish