I'm wanting to upgrade to a larger tank. Right now I have a 5 gallon with a betta and a 10 gallon with some minnows, a cory, and a pleco. I'd love something bigger for my 10 gallon fish. I found a 35 gallon hex tank on Craigslist that I'm interested in, but I feel like I remember reading somewhere that hex tanks aren't the best shape? If I got this tank, would my 10 gallon fish be okay in it? I can imagine they'd like all the extra space, but is the shape a problem? I also found a 50 gallon rectangular tank that's only a little more expensive, but further away, and as I live in a 3 story townhouse, I'm a little worried about my main living floor (where the tank would be) supporting the weight!