NEED OPINIONS ON A CLASSIC DEBATE THAT I'M STILL UNSURE OF

I'm setting up a very large 450gallon 10' acrylic aquarium. money is tight right now so I'm building a cinder block stand with 3 columns. each column will consist of 38 blocks, 2 columns on either end and one column dead center. Next I will have 10' long piece of treated plywood about an inch thick. Now the part that's been a debate forever, do I add foam between the tank and plywood or no? Please give me your opinions and why, trying to have this project completed in next 4 days