Plants not only beautify your aquarium, they consume the end-product of the nitrogen cycle: nitrate.  They also give your puffer places to hide and explore.  I highly recommend live plants for your aquarium.  When choosing plants for your tank, make sure they match your puffer's water conditions.  There are a great many species of flora to choose from.  This page of Puffernet will be expanded soon.  For now, it is UNDER CONSTRUCTION.