I have a 90g on my main floor(on a 3 level house)
It's actually in the middle of the main floor but there is the telepost close by. My tank spand with the beams (parralel) which was quite bouncy.
I never worried about it too much but I did screw my stand into the wall with some ties from HD and I also made an I beam to go in the basement under the main joist that the tank sits on to ellimiate the bounce

Kinda like a 2nd post in the basement.
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No matter what the morrow brings, inventors keep inventing things.
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Jonathan
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