erik, I had a 12o gallon cube w/ a 40 gallon sump and a heavy frickin stand in my apartment... no problems w/ it falling through the floor.
but here is something to think on.
one bad day.
2800$ in repairs to my downstairs neighbor later... no more tank and a heck of a lot of OT to pay for it.
my advice?
while your in an apartment, reign in your cravings and do something more along the lines of maybe a 50 or less. I went from a 120 cube to a 30 cube.
the 120 was totally overpowering the room it was in anyway.
that's just my two cents... a leak in your hose sucks, a leak into your neighbors home sucks more.
"Maybe in order to understand mankind, we have to look at the word itself: "Mankind". Basically, it's made up of two separate words - "mank" and "ind". What do these words mean ? It's a mystery, and that's why so is mankind." ~ Jack Handey