A number of people even have picket tanks, which seem great but in many cases are prone to rot and uninteresting organisms.  Metals are normally not applied due to the corrosion, particularly when addressing saltwater.  Having said that, chrome steel has small more than enough toxicity and can be used, specifically in freshwater techniques. 

Fish or shrimp can be incorporated, but the key draw would be that the aquascape aquarium mimics the natural landscape viewed either above or underneath the water. It could possibly signify forests, mountains, rivers, or any characteristic of a natural landscape. The way in which the hardscape is layered in the tank obscures the substrate solely