Tank Stand / Platform Question...

I'm getting ready to start building the stand / platform for my 120 and was looking for some comments on my plan. Just want to make sure I'm not going build something that's going to fail... The left and right side will actually be above the foundation of the house with some wood in between to raise the height up a little(for sump clearance.) I'm attaching a crummy ms paint diagram that shows what I'm planning. I've got a span of around 40 inches between the foundation and was planning on having either 2x4's or 4x4's crossing the span with posts in the front and back. Does this seem strong, or am I missing something. I built a front porch on my house that hasn't fallen down yet, but I'm way more worred about the tank than I ever was about the porch...

So you're placing the tank over a hole in your foundation? I'm confused.

Nah, not a hole in the foundation. I think when the house was built, the foundation was poured to accept a prefab fireplace. So it's kind of a bump out in the foundation. It's tied in to the rest of the foundation. A not to scale diagram of my foundation:

And sorry -- the construction here in RI may be different than other places. For my type of house, in the family room downstairs, the foundation is actually partially above ground, around knee high.

i personally would go with 4 x 4's approx. 1,200 should be ok. But why three vertical supports in the back and 2 in the front and 0 in the center?

I have my stand pictures on my tank build thread if you want some reference:

https://www.livingreefs.com/wesleys-125-a-t20455p2.html

Have four 2x4 in the back and three 4x4 in the front for bigger opening.