Placement of stones and rocks in an aquarium.
A composition of stones is called Iwagumi. Iwa means “stone”, gumi means “arrangement”. That is, Iwagumi means the arrangement of two or more stones to create a composition. There is a huge number of schemes and rules for arranging stones. Five main types of stones.
Low vertical – Low vertical – the base is wider than the tapering top. A very frequently used stone.
Tall vertical – Tall vertical. A vertical stone with a base just slightly wider than the top. Place with the utmost care – this is the tallest stone in the group and defines the main line of movement of the garden. Never place it in front of other stones!
Flat stone – Flat stone. The most useful stone. In complex compositions, it is used as a central harmonizing element, while in simpler compositions it serves to harmonize vertical stones with horizontal lines.
Branching stone – Branching stone, Shigyoseki. This is a stone with an irregular shape – the top is flat and slightly wider than the base. The most difficult stone to choose; if the top is too large, it looks unstable. This is an extremely useful stone as it is used to connect two horizontal stones with two vertical ones, as well as to unite a group of stones with tree branches.
Reclining stone – Reclining stone, Ox stone, Kikyakuseki. In height, it is between flat and branching, but never lower than flat and not higher than branching. One edge of the stone is higher than the other. This is a fine-tuning stone placed in the front to unite other stones, and must be positioned very carefully.
All these Main stones are used in any number of combinations, and are often combined with Auxiliary stones in any number and of any shape, which should no longer have the shape of the five Main stone types listed above. These Main stone types are used as the main stones forming groups. There can be several groups. In each group of stones, only one of the five Main stone types can be used! The remaining stones of each group have a shape different from the Main ones and simply complement them! You can put two or more stones of one of the five Main types in a group, but groups of three, five, or seven are usually used. Stones of different types are never placed in the same group.
Groups can be combined together (as subgroups) to create a large focal point. For example, a group of three stones standing next to each other cannot be made of two Low verticals and one Flat. Instead, a group of three stones should be created – one Main Low vertical, and two Auxiliary ones of slightly different sizes that do not repeat the shape of the main one. Then make a second group, for example, with a Reclining stone. Together these two groups form a larger composition. Around the groups of stones, for the balance of the composition, you can put any number of smaller stones of any shape, but only those unlike the five Main stone types – Auxiliary ones. Large boulders of stone on one side cannot be balanced with a few small stones elsewhere or driftwood.
You cannot use stones that have been clearly cut or broken; — stones with a top larger than the base; — mix water-worn stones (coastal) with sharp-edged stones (mountainous); Do not place stones so that the axis of symmetry of the stone is at right angles to the walls of the aquarium. Please note that when arranging stones, it is important to place them in such a way that all smaller surrounding stones are directed (tilted) toward the largest (Main) stone in the group. Such placement focuses attention on the main stone of the group.
Sanzon-Iwagumi principle. Plants and stones are arranged using the most important principle of Japanese garden art called “Sanzon-Iwagumi”. This is the arrangement of stones in a triangle. The largest of the three stones is placed slightly in front, the second largest to the right and behind it. The smallest stone is placed to the left and behind. Keep the proportions so that in the front view, the aspect ratio of the resulting triangle from left to right is 2:3. Three imaginary lines between the centers of the stones should form a triangle. If more than three stones are placed, the next triad is arranged according to the same principle, but in a triangle of a larger/smaller size, of a different shape, and shifted relative to the first triad of stones.
Plants are planted according to the same principle, only by interweaving and shifting the plant triangle relative to the stone triangle. By the way, the rule of threes ensures that the number of objects is always odd. When arranging stones of different sizes, they should be positioned so that the cracks are in the same direction, and always cover the base of the stones with substrate. This creates the impression that the group of stones is a single solid stone. This is an important technique if you do not have stones of the appropriate size.
Arrangement of the main stone. The main stone determines the entire impression of the Iwagumi layout. Choose this stone, carefully considering its shape, size, and individuality. Since the main stone is the most important, please consider all aspects, including its position, tilt angle, and tilt direction. By placing the main stone in the center and tilting it to the left, you forever remove the center of gravity of this aquarium from its geometric center.
Arrangement of the supporting stone. Then you place the second largest stone, the supporting stone, against the main stone and tilted away from it. Now we will adjust the directions and tilt angles of the two stones, and carefully determine their position. In a composition, arrangement usually starts with the main stone and ends with the smallest.
Arrangement of supporting stones. The next five supporting stones (3-5). Now we will add smaller stones, directing their tilt to enhance the supporting stone(s). Arranging these stones in a zig-zag pattern will enhance the sense of depth in the composition. Placing smaller stones (6) between larger stones will unite the composition and give it a natural look.
Creating hills around the stones. Creating a slope from the foreground to the background, we pour sand between the stones and continue the line of the composition. Do not put too much sand in the foreground.
Planting. Planting is easier if the aquarium is filled with water just above the sand. We place small stones with Riccia along the line of large stones. Then we plant Hemianthus callitrichoides in the front and Glossostigma in the back. The use of short-stemmed plants with small leaves enhances the perception of the stones.
Planting plants between the stones. We plant the next 5 supporting stones with Blyxa rovoguineensis leaf and Echinodorus tenellus. Planting around the stones from all sides is very important, it gives a greater naturalness to the composition. At the end of planting, both plants and stones look more natural.
Filling the aquarium. In the end, we choose Eleocharis vivipara for the background. Eleocharis also lightens the impression of powerful stones. The planting area depends on the balance of the composition. We plant to the left behind stone 2. After that, carefully so as not to knock over the stones, we fill the aquarium with water.
Giving stability to large stones.
1. You can give stability to a stone placed in the aquarium by attaching “legs” made of a strip of Plexiglas to it. To do this, saw off a strip of the required size from a piece of Plexiglas (for a small flat stone 30 cm long, 12 cm high, and 4 cm thick, a 6x8x150 mm strip was enough for me), heat it all near the flame of a gas stove, holding it by the ends, until it becomes pliable, resembling dense rubber. Here it is necessary to be careful – Plexiglas loses transparency upon local overheating, boils, and burns very well, so it is better to heat it not over the fire, but near the fire, monitoring the uniformity of heating along the entire length.
While the strip is hot, tightly grasp the stone from below with it, press firmly, and wait for it to cool. Make sure that as a result, the stone “lies on its belly”, supported by legs on both sides, rather than “standing on its hind legs” – this way the mass of the stone is better distributed along the bottom of the aquarium, without creating unnecessary load points, and there is no need to test the Plexiglas for strength once again. Let me remind you that under heavy stones, before placing them in the aquarium, it is necessary to put a piece of thin polyurethane foam.
2. Everyone knows the problems with stones in an aquarium: • accumulation of dirt under the stone; • risk when installing large stones due to large uneven (point) pressure on the bottom, the bottom may crack.
There is an idea how to avoid all this using polyurethane foam:
• Plastic film is laid on a flat surface (so that the foam does not stick, they take a square of chipboard and wrap it with film).
• Pieces about 5 millimeters thick are cut from a bottle cork – lining “tablets”.
• The stone is soaked in water so that the polyurethane foam adheres well and is stably placed on the “tablets”.
• Polyurethane foam is injected under the stone from all sides.
• The next day, the excess foam that came out around the stone is cut off, and the stone gets a perfectly flat base. After that, the stone together with the foam must be soaked in water for 2-3 hours.
• For safety, the stone is placed in the aquarium before filling the substrate; when the substrate is filled, the foam base will not be visible.
Using driftwood in aquarium design. Basic compositions.
Using stones in aquarium design. Stone shapes. 
Last changes and additions were made on August 23, 2012.
