HAHA, wouldn't that be cool? A whole HOUSE full of fish!
Seriously, I would get the biggest tank you can fit and afford. You'll appreciate the room once you get into it, and also, the maintenance is much easier on big tanks

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This link may be helpful:
[URL="http
/alysta.com/books/fishtank.htm"]http
/alysta.com/books/fishtank.htm[/URL]. It has the dimensions of standard tank sizes, although in gallons....just do a little conversion. Also, don't forget to look at used tanks. This from a college student, used tanks are much more affordable and not too much extra work, depending on the tank.
Laura