Leveling an aquarium stand

[NE reefer]

Hello everyone,
I’m working on a DIY stand/canopy for a 90 gallon tank with a rim. I’m new to wood working and have run into a potential problem.
The design is 2x4 frame , covered with pine that I distressed and stained to look like barn/drift wood. My plan is to place a sheet of plywood on the top of the frame that the tank will rest on.
However I’m just now discovering that my tank is not perfectly level.
My plan is to use neoprene foam mat between the stand frame and plywood top.

How much effort should I put into adjusting things?

 

[PotatoPig]

Don’t put a foam mat under a rimmed tank - they’re not designed to work that way and AFAIK all manufacturers tell you not to.

Your best bets are to shim the stand legs to get it levelAND/OR put the empty tank on the stand and shim under the corners.

The manufacturers of rimmed tanks (AFAIK) tell you to make sure he corners are fully supported- this is where the loads need to go.

 

[Rjukan]

However I’m just now discovering that my tank is not perfectly level.
My plan is to use neoprene foam mat between the stand frame and plywood top.

I'm confused, is your tank not perfectly level ie. it won't lay flat on a known flat surface? Or is your stand not level which is in turn affecting the tank?

 

[NE reefer]

I'm confused, is your tank not perfectly level ie. it won't lay flat on a known flat surface? Or is your stand not level which is in turn affecting the tank?

Tank is perfectly square and level. The top of the stand isn’t perfect. I’m wondering if I put 1” strips of leveling foam strips under the rim of the tank would it allow the tank to sit more level on the top of the stand? Below is the description of the leveling strips I was thinking about using

Neoprene Rubber Strips Self Adhesive Solid Rubber​

 

[Rjukan]

Tank is perfectly square and level. The top of the stand isn’t perfect. I’m wondering if I put 1” strips of leveling foam strips under the rim of the tank would it allow the tank to sit more level on the top of the stand? Below is the description of the leveling strips I was thinking about using

Neoprene Rubber Strips Self Adhesive Solid Rubber​

No, just like @PotatoPig said, you don't want to use foam or anything on a rimmed tank.
Just use the plywood top like you were going to, set the stand in it's final location, then use shims to level the stand so that the tank is level.

 

[NE reefer]

All advice is much appreciated. Thank you. My main concern was tank stability over time.