I have a 75 gallon tank in my recently constructed room, we tore down a sun-room and put my room on it but its not on solid ground, theres a concrete outline of the foundation then we created a new floor with wood. the stand and tank arent all that heavy, but i did the math and filled with water alone it will weigh about 860 pounds. does anyone else have experience with a floor like this, anyone unlucky enough to have experienced a cave in? everyone is telling me it will be fine but i want to be sure. i have a 45 gallon tank in my living room thatb is above my basement and it is fine, somone reassure me......