Hi TH...
DIff p-ple have diff opinions/ ideas etc...
Some like the nano concept...if u have $$ to spare n only wanna try out...then maybe u can have a nano/ small tank concept. But believe me...once u get hooked on...u sure wanna upgrade ya tank size..cos the ocean has so many interesting stuff to offer....& by upgrading ya tank would prob means wasting $ on ya first set-up (lights, tank etc)...[though some p-ple manageto find buyers/ recycle their stuff]
However, should u decide on a small tank...pls becareful wif wat u r buying...due to the limited size of the tank.
Personally i think that a 2feet tank will be a more reasonable try for a beginner.
Hope this helps!