Foam under your tank or sump?

[Matt_Wandell]

We use FRP grating or beams under our acrylic tanks and sumps to create a flat surface on non-flat floors. Acrylic needs to sit on a nice flat surface. If it's not perfectly flat, I would agree that foam will not fix that problem because pressure points will still be created.

For reasonably sized tanks, I like to use Dri-Dek underneath them. Please note that the point of this stuff is NOT to smooth out uneven surfaces, but to create an air gap beneath your tank to make cleaning up spills much easier.
http://reefbuilders.com/2010/04/28/dridek-rubber-matting-save-carpet-hardwood-possibly-marriage/

 

[gimmito]

Love FRP !

 

[Kmooresf]

That Dri-Dek seems great. Anyone know how it would handle the weight of a 400 gallon system? Just wondering if it would still allow air to pass through if compressed that hard?

 

[rygh]

That Dri-Dek seems great. Anyone know how it would handle the weight of a 400 gallon system? Just wondering if it would still allow air to pass through if compressed that hard?

While the overall weight is huge, the pounds per square inch is not so bad, because the footprint of the tank is large.

A 2 foot high tank is only 0.9 pounds per square inch.
Yours truly, standing still, is very roughly 4 pounds per square inch.
(Big guy, but big feet)

The unknown though is if over a long time, it slowly crushes down.