Can my floor support a 375 Gallon tank?

[millerkid519]

The only thing I do not like the more I look at the picture of his floor joists is that they are engineered joists. Which means they use chipboard in between 2-2x2 runners. Compression of the floor joists may become a huge issue. If you are going to do this I would for sure be sistering the joists together

 

[skjl47]

they are engineered joists.

hello; I saw that as well. The nice thing about such joists is they tend to run true and I think can be had in many lengths. As with man engineered products the quality can vary.
I have never sistered these type but would guess sheets of plywood glued and screwed on both sides of the chipboard.