What to do with this uneven rimless stand

[Visionist]

I'm more or less at my wits end with this stand situation. I bought a fluval flex 15g rimless tank and needed a suitable stand. I set out to build one and I've run into an issue, the plywood for the top(which is 3/4 inch thick) has a bit of a bow in the center. I really don't have the equipment or time to attempt to sand it down to be perflectly flat. I've built stands before with no issues, but never for a rimless tank. The tank came with a 3-4mm thick black foam that is fairly squishy
What should I do? The gap from the plywood appears to be around 1-2mm, it's hard to tell quite exactly
Would I be better off chucking some MDF on top of the plywood since MDF is about as flat as it gets?
Would high density(pink) foam solve this? However people say its too rigid for rimless
Should I just burn the tank and the stand and walk into a busy street?

Note: The plywood top has not yet been glued/screwed to the stand

 

[Regular_Reefer]

My stand was just slightly uneven when finished, maybe from the heat and shipment. I used some of those plastic shims that you would find in the bathroom plumbing section of you LHS. Slipped them in place once the stand and tank see where I wanted it in the house. They worked perfect for me. I think they are commonly used to level toilets lol but if it works it works.

 

[bevo5]

Maybe try another/flatter top piece?

 

[Regular_Reefer]

Here’s a pic

 

[Tono]

That doesn't look like it's that warped. I would maybe consider using a piece of thin styrofoam sheet between the plywood and tank and ensuring that the bow is concave if viewed from the top.

 

[Regular_Reefer]

Depending on the stand you could also shim the top with carpenter putty and slivers of wood (scraps) just place them evenly and thick enough to support weight