I like this idea alot, I just may have to try it!I used pottery clay to build barriers (upside down T shaped when viewed from the ends), fired them, put them in during setup and it kept the back high. It also prevents your background plants from encroaching further into the tank. Could also be used to build different levels around a tank.
Metal sheets aprox. 4 x 7 in the the gutter area of hardware store.Metal sheets? Why type of medal?