This is really based on personal preference.
I see you already have the 180, so I don't want to insult your intelligence, but I have seen way to many posts regarding disease and fish incompatability from others, and I even had a little bout of bad luck due to impatience recently. Whatever advice you receive via the message boards, please research, research and research some more before you take others word for what will work well in that size and together, and make sure you pay attention to adult size and not just the size at purchase unless you have a plan to trasnsplant the livestock later. Many fish that we like will grow far too large for a 29 gallon tank.
Also don't forget quarantine... Everything that is wet should be quarantined before entering the display.
Sorry I didn't address your actual question, but I just wanted to put my thoughts out there.