OK, think I muddied the waters just a bit with my description. All load bearing walls, beams and piers in this house run east-west............Tank will be situated north-south, parallel to the joists, but perpendicular to the beam, the center of the tank crossing the beam and straddling it...............Hoped that clarified things a bit.......Guess that n/s, e/w stuff was a bit confusing.........I sited the house on the compass points and I tend to think of things that way, but it can be confusing trying to explain that to someone else..............You may not be an engineer, but clearly you have more experience and knowledge in these areas than most people, myself included.........I'm 65, but smart enough to know what I don't know and always appreciate good advice.............Yes, you're right, most any solid floor will hold any "reasonably" sized tank without collapsing, but outright failure isn't the only potential problem.............7 years ago I set a 125 in a different room of the house, against a non load bearing interior wall, perpendicular to the joists and at the end where they rest on the beam below. There is a basement under that tank and I jacked the floor at two points below the tank prior to filling to alleviate some/most of the stress from a 1500 pound tank. everything is still plumb, level and square and the tank is still there...................all my cats were feral, sick, homeless or just strays. They show up, at deaths door and I take them in. 5 more buried out back that died of old age.
Thanks for the input.