Thank you!
The fish room floor is 100% fine. It's sealed and painted concrete, and the walls next to my sump are waterproof, with a nice thick bead of silicone between the wall and floor. Minor floods are inevitable, so I just planned for them.
My display tank is sitting on a tiled concrete pad that extends about 8" beyond the stand, so minor drips and splashes there aren't an issue either.
yeah thats how I have mine done now, my real bad flood in this hobby happened when I still lived on the second story of my apartment...i've since learned from my mistakes