I am getting my 500 gallon acrylic aquarium back tomorrow. I had a crack repaired in the bottom. The man that repaired it helped put the acrylic windows in the reef tank at Shedd Aquarium in Chicago. The acrylic was 8" thick they used fork lifts to put the panels in the aquarium. I live 40 mile from the Shedd Aquarium. I should go take he train into Chicago and see the fish. I don't drive in Chicago because of the camera lights all over. I like a tank with no substrate, I will have to have one now because of the ugly repair on the bottom. It's easier to keep the water clean without a substrate. It costs $39 each to go to the Shedd. They have 50 free days a year. Do other people have trouble with typing on this web site. I have to constantly edit what I type. Maybe I should write what I want and copy and paste it here.