Thanks for all the tips.
I hate that the floor needs dealt with first, since it has to possibly wait for next year and I want to get started now!
I've narrowed my options down to:
1) Strip the paint off the floor, sand it down, and resurface it. Depends on the floor being in good condition which is a big unknown.
2) Repaint the floor. Hate the idea of a painted floor, but it's cheap and quick.
3) Tile. Could be ... interesting doing this as a DIY project with no experience in tile work.
Ideally i would like to do number 1, but it requires the windows being open for days which just isn't possible this year (too cold out). Tile concerns me because of the added height it would put to the floor. I'm not sure if it would be much higher, or equal than the carpet + pad that is down right now.
For the tank stand itself this is what I have sketched out. It's the same basic concept as what I linked above, but modified some to make it more robust in my opinion. What do you all think? This is just a sketch of the basic shell. I would add paneling and trim to make it look better, but that wouldn't add anything structurally.