I have a large aquarium located in a cold room in my house. In winter the temp often goes down to 50 degrees. I want to keep the aquarium at the right temperature, but I don't want to spend a small fortune on electric bills. What is the best way to insulate this tank, and where would I buy the materials? Ive been thinking about one of those plastic small shrubbery covers they sell in garden supply stores. Anyone else have this problem? How did you solve it?