Cost of building larger tanks

[sphelps]

I think in general cost setup cost is more related to tank length than volume, for example a 55gal wouldn't cost much less than a 4' 120gal to setup other than the tank itself. However if you go with a 6' 120gal the cost will be higher due to the extra lighting, flow, and stand requirements. Realistically though your overall cost is more dependent on what you keep and the type of equipment you choose to go with, for example I've setup smaller, almost nano, tanks that cost more than some six foot tanks.