I had Fort Collins plastics custom cut a piece of acrylic for my biocube and my shallow reef. They even cut tiny feeding slits. Materials plus labor was $40, which is a great price for the quality of work they do. If it's a large piece, you might want to add some bracing because it does sag after a while (I flip mine over once a week). All you need to do is walk in with the dimensions or an outline. If you want any bracing or feeding holes, tell them where. It's all done with a electronically so you get a perfect edge. Let me know if you want more info.