Fear of falling through floor! Real or Not?

[Psyire]

I was worried about this as well when I put my 180g + sump on the second floor of my place.

I have about 220g of water on the second floor, without any additional bracing. However I do have it near a support wall and perpendicular to the floor joists. I routinely check it for level and check the floors and wall seams fairly often as it is a concern.

On that note, I haven't seen it move at all and it's been up and running for 3 months now. This kind of question is always situational though, as every house and tank is different.