Check it, if it's not the right thickness, buy a nice snake. I'm thinking Brazilian Rainbow Boa, a little aggressive, but if you start with a juvy it'll be a walk in the park,
. Seriously, check it first, it might just be a fish aquarium that just happened to be cheaper at the time than a reptile tank. I wouldn't worry about it until you measure the glass. I don't really remember but back in one of your first threads you said something about it not mattering what the cost was. Well, I don't know if that's the case, but remember that a 55 will be more of a cost to setup, and you use more saltwater on water changes than you would with a 29. I agree that the bigger the better. However, if you get a 55 gallon it'll be more permanent if you crash it and decide you don't wanna do it anymore. Which I doubt will happen, but there is a certain point where it gets discouraging, for me anyway. I started with an 18 gallon, it was a crash course. If you go with the 29 gallon you need to stick to a definate schedule on water tests and water changes, especially if you don't get a protein skimmer for a while. I feel you should get a 29, I think it would be more of a learning experience and force you to want to learn even more, that's how I feel.
Just my 2 Abes
Clint
OK that was more like an entire dollar of cents, but hey, I wanna try to help, I'll try to keep things more brief.