Floor - To brace or not to brace??

[gregzz4]

OK, I'll ammend my previous suggestion and go with this ;

Put the tank in the location, fill it, bounce around the room and see if the tank rocks or stays put

BTW, I'll bet you dollars to donuts that it will rock the tank when you bounce on the floor, or it will at least eventually crack the seals on the trim to the floor

Good luck with whatever you decide !