An excellent place to start would be with a brief background of what Nano tanks actually is exactly what they are, simply dwarf versions of the larger tanks we keep in the hobby and normally restricted to tanks 20g and under. The principles are all pretty much the same, just scaled down obviously for the reduced amount of space and water available. It is still just as successful to use natural methods of filtration, and this really allows for a fairly inexpensive way to start off keeping saltwater livestock.