Hello. I think this is the right place to post my question... So I keep getting asked to ship my acrylic tank, every company wants to know weight. Is there a way to calculate weight? I know its heavy. But they want more detail than that obviously... If someone could help me figure it out, that'd be awesome! I guessed 500lbs, but I honestly have no idea... The dimensions are: 72inx72inx20in then the acrylic is .67in thick. Thanks for any help!