What Iwagumi means
Iwagumi is Japanese for "rock formation". It is the most minimal aquascaping style: an odd number of stones of one kind, arranged around one clearly dominant stone, over a low carpet of one or two plants. There is nowhere to hide a mistake, which is why it is admired and why it is hard.
The stones
- Oyaishi: the main stone, clearly the largest, set about a third of the way along.
- Fukuishi: the second stone, beside the main stone and leaning the same way.
- Soeishi: smaller accent stones that support the main pair.
- Suteishi: a "sacrificial" stone, often half buried, that balances the layout.
Use 3, 5 or 7 stones of one type, most often seiryu or dragon stone. The planner checks the count, that one stone is at least a third bigger than the next, that there is no wood and that the main stone sits on a third.
Carpets and care
Classic carpets are dwarf hairgrass, Monte Carlo and HC Cuba. All grow fastest with bright light, CO₂ and a nutrient-rich soil, and many keepers grow them in from a dry start before filling the tank. Without CO₂, Marsilea crenata and dwarf four-leaf clover are slower but forgiving. Keep the fish small and in one school, such as rasboras or white cloud mountain minnows in an unheated tank, with Amano shrimp to graze algae off the stones.
Other styles
- Nature aquascape planner
- Dutch aquascape planner
- Jungle aquascape planner
- Biotope aquascape planner
- Low-tech aquascape planner
New to the styles? Read Iwagumi vs Nature vs Dutch, or start from the main aquascape planner.
Questions
How many stones should an Iwagumi have?
An odd number, usually three, five or seven, of one stone type, with one stone clearly the largest.
Can you do Iwagumi without CO₂?
Yes, with slower carpets such as Marsilea crenata or dwarf four-leaf clover. Expect it to take months to fill in, and keep light moderate so algae does not outpace the carpet.
The aquascape planner is in beta. If something looks wrong or you would like a plant added, tell us.