To Foam or not to foam

I'm setting up dual 10 gallons on two stands (4 tanks total). Double layered plywood on the bottoms. In the picture I have 1" yoga mat foam under the tanks, as I thought maybe it would just help level and fix any stress points. The plywood is fairly level but I was doing this as extra precaution, since I'll be keeping expensive shrimp in them.

So, is the foam needed or not? If yes, is 1" foam too thick? Any advice appreciated.




Edit: foam is 1/2"

 

As long as the tank is supported on the 4 corners you should be fine. For my 40 breeder build my stand was uneven since I didn't level it while building. The base of the tank was fine since it was going on a rug. However the top isn't completely flat, I added foam since I wanted the weight to be spread out instead of having a piece of wood or two to be taking most of the weight.

 

The foam might cause the tank to flex more if it's not level. Flexing causes cracks

 

Sounds like it is "not to foam."

 

Sounds like it is "not to foam."

Give it a go, some people have them on rugs

 

No foam. You want all four corners on a firm surface.