He, or she should you get a female, will indeed do fine alone. They're recommended to be gotten in a male/female pair in many forums, this one included last I looked....however, whenever I get them in pairs for my bigger tanks(I've gotten three different pairs, so I suppose that's not much, but my aunt always had the same problem and she kept trying wanting to breed them for years, and did succeed a few times, but the trouble never ended with the pair), they always, -always- make trouble and bully and chase and fight. I've never had problems with singles though, they seem perfectly happy to just check things out and swim around owning the place. lol
Hmm, look into an angelfish too. They do well in either a single, triple or so on. More need more room, but one might be do-able. Don't quote me on that though, I can't remember if one can go in a 29, though I know many do in fact keep them in 29 gallon tanks(other people doing it doesn't mean it's a good thing so be sure to check if one CAN go happily in a 29g), so if you're interested in any type, or I should say color morph of angelfish, look into that one.