Tank on second floor.

[reefwars]

i had my 180 plus 50g sump in my living room as long as you stay as close to your exterior walls as possible. a load bearing wall would also be fine .theres a better chance of your stand colapsing than your floor lol also make sure you cover the floor with plywood or something so as not to damage your flooring

think of it like this your bathtub filled with water with two people in it