styrofoam under tanks

[kole]

My new 180 has arrived! I built my stand and have checked it for level and square. The tank I have has a flat trim on the bottom not the trim that raises the bottom pane of glass 1/2 inch. The bottom pane is only raised the height equal to the width of this flat trim probably 1/8 of an inch. So I want to know what I should place on top of the stand between the stand and tank.
Couple of ways I have considered and have been searching online about.

1) I could place the tank directly on the 2 X 6 rails nothing between tank and stand with open top tank.
2) place plywood on rails and tank on plywood
3) place 3/4 styrofoam on rails then tank on styrofoam
4) place plywood on rails then styrofoam then tank

Any suggestions which way would work best or what way do you have your large tank placed. Take in consideration the type of trim on the tank. Thanks
Please post with anything you have experienced. I know it has been debated a lot but I want to do it right.