Thanks!
Does the poly pad have a distinct name brand that works best?
How well do heat pads work if put against the side glass on one end? There is one here: Amazon.com: Fluker's Ultra Deluxe Premium Heat Mat, Large (17 x 11 inches): Pet Supplies That looks like a good fit size wise for my tanks end pane. Would/does this type of heat work from the outside well?

Thanks again.
Doug