Lol wow, mention having 25 tanks and watch your thread grow!
I've been keeping fish for 15 years, started when I was 8. While living with my parents, they wouldn't let me have any more than I could cram into my bedroom, and nothing bigger than a 20gal, so I only ever had like 5 going at the time. But when I moved in with my boyfriend about three and a half years ago, things kind of went nuts from there, and we got up to 25 pretty quick.
They're not all big tanks, not by a long shot. They range from 5gal up to 90gals for the monsters, and every size inbetween basically. They're in just about every room, too...there's three in my bedroom, two in one spare room, four in another spare room, whole bunch in my living room/dining room (basically just one big room), and all the bigger ones are downstairs on the cement floor. I'm hoping to squeeze one more in down there if I can, but it will be a BIG one, at least 150gal or bigger. I'm trying to hold off until we move though - we currently rent this place, and it's only a duplex. Moving when we finally buy a house is gonna be totally lame.
