How to Aquascape: Iwagumi Style

An Iwagumi aquascape is a style of planted aquarium. It usually focuses on the beauty of the rocks. The style is inspired by traditional Japanese and Chinese rock gardens. The stones are chosen carefully to create a peaceful and natural-looking landscape. The goal is to use rocks with interesting textures, shapes, or patterns as the main features of the aquarium.

Traditional Iwagumi Style

A classic Iwagumi layout usually follows a simple and minimalist design. It usually uses one type of rock throughout the aquarium. An odd number of rocks (such as 3,5,7, or 9) is arranged in a very natural-looking pattern. One large rock serves as the main focal point. However, the smaller rocks support and balance the overall design. A single species of carpeting plant is planted around the rocks that cover the substrate. It creates a clear and harmonious appearance. 

Modern Iwagumi Style

Modern Iwagumi layouts keep the same natural look but allow more creativity. Different rock sizes are combined to create more realistic landscapes. Some of the rocks are arranged into cliffs, ridges, or rocky hills. The substrate can be shaped into hills, slopes, or valleys to add depth. Some of the decorative sand is left exposed in some areas to create contrast. Instead of using only one plant species, you can add multiple plants and maintain a simple and balanced design.

How To Choose Rocks For An Iwagumi Aquascape?

The rocks are the main features of an Iwagumi aquarium, so you need to choose the important ones. 

Large Main Rocks

Your main rocks should be at least three-quarters (75%) of the tank's height. A large rock creates a strong focal point and makes the aquascape look more natural. You need to keep in mind that the rock will appear smaller when you place it in the aquarium because part of it will be buried under the substrate. It can be tilted to create a more natural angle. 

Carpeting plants will cover the base of the rock. Most beginners choose rocks that are too small. It can make the hardscape look less impressive. If you can't find one large rock, you can combine various smaller rocks to create the appearance of a larger rock formation. However, it takes careful planning to make sure rocks match in color and texture. 

Shape and Texture

If the rocks have sharp, triangular shapes, these are easier to arrange because they can create a natural flow and direction in the layout. 

However, you can also use other shapes if they fit your design. So, look for the rocks with interesting textures, natural cracks, and the same colors and patterns. When you use rocks with matching texture, it helps create a more realistic and balanced aquascape. 

Different Sizes of The Same Rock

In nature, large rocks can naturally break into smaller pieces over time. If you want to recreate the look, use rocks of the same type in different sizes. When you use a mix of large, medium, and small rocks, it helps create smooth transitions between the main rocks and the substrate. Your aquarium looks more natural. 

It adds depth and detail, especially when you are using decorative sand. Some rocks, such as Ohko (Dragon Stone), lava rock, and shale, can be broken into various pieces. Others, like limestone, Seiryu stone, and granite, are much harder to break. 

These usually need to be purchased in different sizes. When you choose rocks that are large enough, make sure they have matching textures and come in a variety of sizes that help create a balanced and natural-looking Iwagumi aquascape.

How To Prevent Algae in An Iwagumi Aquascape?

Feed Plants Through The Substrate

Carpeting plants can absorb most of their nutrients through their roots. The use of nutrient-rich aquarium soil or the addition of root tabs can give them the nutrients they need without adding too much of the fertilizer to the water. When you keep lower levels of nutrients like phosphorus and nitrogen in the water, it can reduce algae growing on rocks and decorative sand. 

Here is What Aquascapers Should Know About Dirted vs ADA vs Inert Substrate.

Use Moderate Lighting

Many people think that carpeting plants need very bright light, but it is not always true. When there is a good CO2 system, carpeting plants can grow well under moderate light. However, too much light can increase the algae growth, mostly on rocks and glass. Moderate lighting can help keep the aquarium cleaner and allow plants to grow and spread. 

Check out LED vs T5 Aquarium Lighting.

Keep The Tank Clean

Iwagumi aquascapes usually have fewer plants than other planted aquariums. So, they have less natural competition against algae. It makes regular maintenance even more important. You should not overstock the tank with fish and remove leftover food and waste regularly. Do a regular 50-70% of the water change every week to maintain good water quality. When you keep organic waste low, it makes it harder for algae to take hold. 

How to Keep Your Aquarium Clean and Thriving?

Balance Light And Nutrients

High light combined with most nutrients in the water mostly leads to green algae on glass, rocks, and decorations. Stronger lighting can help carpeting plants spread faster, but it also increases the risk of algae. You need to follow a balanced approach with moderate light, proper CO2, and regular maintenance. It usually produces healthier plants and a cleaner-looking aquascape.

How To Arrange Rocks In An Iwagumi Aquascape?

The way you place your rocks is equally important as the rocks you choose. There are a few simple techniques that can make your aquascape look more natural and visually appealing. 

Show The Best Side of Each Rock

Every rock has a unique shape, and some sides look better. When you place a rock, rotate it to find out the most attractive angle. You can also tilt the rock or use smaller stones that can support it. When you do so, it allows the best side to face the front of the aquarium. Look for some of the interesting details such as ridges, cracks, and textured surfaces. It makes the rock stand out. 

Tilt Rocks For a Natural Look

Instead of placing rocks perfectly upright, you need to tilt them a bit. It creates a more natural appearance as if the rocks have been shaped by nature. Tilting the rocks also creates light and shadow. The side facing away from the light becomes darker, and the side exposed stays brighter. The contrast makes the rocks look more three-dimensional and adds depth to the aquarium. 

Keep The Design Consistent

You can use the smaller rocks that match the larger ones in texture, color, and shape. Place them around the main rocks that can create a smooth, natural transition. When you keep a consistent style throughout the layout, it can help the entire aquascape look balanced and realistic. Even if it was formed naturally and not arranged by hand, it can still look real.