I'd advise u start by getting some1 to check the building for it's structure.
A tank that size is a problem but it depends on the weight of the filled up tank and then the floor the type of wood the way it's layed out (jus accross the room or if it has and thing to setenthen the floor. It's all a bit confusing but if you could post more details it would help and also it also depends on the location of the tank and how the floor is connected to the walls and the age of the building