Rubbermaid totes and other plastic tubs may seem like a very inexpensive yet effective way to make a sump or a refugium. The totes are cheap, usually under $20 and a large enough to hold protein skimmers and other equipment. Unfortunately, the plastic on these containers is very thin, and when you fill them up with water, they bow significantly. This can eventually lead to the tub failing, spilling water all over the floor. A simple solution to prevent the bowing is to build a wooden frame to help the tub keep its shape.