Very good example of an Iwagumi design in a small ~5 gal tank.
Iwagumi is an aquascaping style in which the focus is on the rocks placement, and the whole aquascape is of a minimal nature. Read more

Tank Specs:
Filter: Eheim 2211 with glass lily pipes.
Lightning: ADA Solar Mini (27 watt)
Substrate: Aquasoil Amazonia, white sand, gravel
Hardscape: Seiryu rocks
Fertilising: Tropica Plant nutrition plus, pressurised CO2.
Plants: Microsorum sp. "narrow", HC, weeping moss and Staurogyne sp.
Fish/inverts: White cloud mountain minnows and cherry shrimps.