That is a big tank ... well over 1600lbs. It is a good idea to get a structural engineer to look over the house plans to see if it is safe for such a large load.
The key to load capacity is the joist size & spacing, and the joist span (those numbers we can't get from the pictures). Also important is where you intend to put the tank. If the tank is sitting directly over top the beam & 4x4 supports going to concrete footings, you *should* be OK as long as the load is distributed over a couple posts. But any where in the middle of the joist span & I would not sleep well at night without additional supports.
To repeat - I am not a structural engineer, and a big tank like yours over a wood floor should be looked at by the pros.
80 gal FW with 30 gal DIY wet/dry/sump.
9 fancy golds, 1 hillstream loaches, 1 rubber-lip pleco (C. thomasi), 3 SAEs, small school of white cloud minnows, planted.