To Build, and to Rebuild
To me building a tank is a hobby unto its self. Something you do for the fun of it, not to save a buck. You probably wont save any money building a tank unless you get the glass cheap. Rebuilding a tank, however, is a great way to save money... and learn how to build a tank. I found an old 70G for cheap and rebuilt it with $24 worth of silicone. It is better now than the day it was first sold. The tear down and seal removal is pretty time consuming so I wouldn't do it again, but it was a great way to learn how to build a tank without having to pay full retail for the glass. Someday I'll use what I learned to build myself a custom, 16mm 100G starphire tank.