Saltwater Aquarium Decoration and Background

Saltwater Aquarium Decoration and Background is extremely important, as it exerts a decisive influence on the visual impact of the aquarium - and the pleasure derived from a beautiful scene is surely one of the main satisfactions of fish keeping. However, do not get carried away, and make sure that the overall effect still has a natural look.

The Role of Decoration
Decoration is necessary for some animals and plants to feel at home. Shy fish look for permanent hideaways in it, while others find the refuge they need to reproduce, laying their eggs on vertical or horizontal rocks.

Even if the residents do not make use of the shelter provided, the decor gives them physical reference points, which allow some species to mark out their territory. These observations are equally applicable to invertebrates, some of which - Anthozoans, for example - live attached to elements in the decor.

When an anemone is first introduced into an aquarium, it is not unusual to see it move around before establishing itself in the spot best suited to it. The decor also provides a support for certain types of algae in saltwater.

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In saltwater, decor sometimes serve as a support for invertebrates that live attached to it.

Finally, the decor allows you to hide equipment, mask the glass panes, and cut off the rear corners, thereby providing a backdrop and bringing harmony to the aquarium overall.

Main Characteristics of Decoration
Apart from the search for a visual effect and a natural look, some rules must be respected when you are designing your decor. It must be functional, accessible, and easy to maintain. The material used, except in rare cases, must be neutral, i.e. it must not modify the characteristics of the water. It must also be solid enough to resist fish like Cichlids, which like to rearrange the furniture.

Of course, the decor increases the weight of the aquarium. Calculate for an average of 60 kg per square meter, although it will be a great deal less if you are using artificial materials. Once again, do not forget that the decor must be put in place before the bed is laid.

Decoration in Saltwater Aquarium
Tropical marine fish live in an environment lacking rocks but, on the other hand, abundant in corals and other elements that can be used to form the decor for an aquarium.

Corals
Calcified coral skeletons can be used for decor. They are often rough or sharp-edged and their stiffness depends on which species they belong to. They come in different shapes and sizes, and, with a few rare exceptions, are whitish in color. Bleaching them results in a perfect white.

In aquariums, dead corals often gradually accumulate a covering of green algae. In this case, wash and brush them under running water and then soak them in bleach (1 sachet of bleach for 10 liters of water) for 1 week.

Coral skeletons are one of the classic elements of saltwater aquarium decor.

This will not only whiten the skeleton but also destroy any organic particles that may have settled in it. Then rinse thoroughly and leave to dry in the open air for at least 8 days. Do not apply this treatment to corals from the Tubipora genus with a colored skeleton. These must be cleaned with a soft brush in hot water and dried as above.

Other Elements of Animal Origin

Gorgons produce a dark skeleton that often gradually decays and even ends up crumbling. They must only be treated with hot water, never with bleach.

It is also possible to use the shells of mollusks (clams for example). Brush and wash them in hot water before putting them into the aquarium. Some aquarists consider shells as potential traps for accumulated waste products, but they can also provide a refuge for small fish and, in the same way, crustaceans.

Live rocks can also play an important role in the decor of an aquarium.

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Gorgons have a dark skeleton that makes an attractive
decorative element.

Artificial Decoration
Modern artificial products are rapidly growing in popularity, especially in large saltwater aquariums. Their main advantage is the creative freedom they give to a fish keeper, making it possible to choose decor that fits his or her exact requirements.

Two main types of material are used: polystyrene and polyurethane. They are both light and neutral.

Polystyrene
Available in blocks or sheets, it is usually used as a protection against bumps and heat (in some house-hold electrical appliances, for example). You can recycle it or buy it in a store. Small-grained polystyrene is preferable as it is stiffen It is very light and floats on water, so it must therefore be fixed into the aquarium. Polystyrene can be prepared to meet your requirements before putting it into the tank.

• Polystyrene decor
Use a serrated knife or small saw to cut the cold blocks or sheets, or you can work with heated polystyrene, with a portable blowtorch or hot-air paint stripper. Be careful when handling polystyrene as it can melt, catch fire, and emit toxic vapors.

To make this type of decor, cut a block in the size and shape you need. If you are using sheets a few centimeters thick, you can heighten the relief by putting several sheets on top of each other. These are stuck together using resin mixed with sand. The design shown can be completed with other pieces of polystyrene, which can partially mask the side panes.

You can also combine sheets with large or small blocks. Then burn the parts that are visible to give them a natural look.

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Decor made of polystyrene sheets: the entire sheet can be placed vertically against the back of the aquarium.

At this point natural elements such as rocks or coral skeletons can be added, and resin and sand are applied to the structure (apart from the natural elements), before clearing up with a vacuum cleaner. This whole process is usually completed outside the aquarium, as it is more practical, and the decor is then stuck to the glass panes with silicone glue.

Polyurethane
Polyurethane foam can be made from two components mixed together, but it is also available in aerosols that are more practical. The product released rapidly increases in volume and solidifies in a few minutes. It can then be sculpted with sharp instruments.

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Polyurethane is increasingly used for decorating large tanks. Here it is combined with cork bark.

• Polyurethane decor
Before taking the plunge into the construction of polyurethane decor, it is advisable to watch somebody else perform the same operation first, to avoid making mistakes. In this case the decor must be created inside the aquarium. If you have made the tank yourself, it is also more practical to put the decor in place before adding the front glass pane, as this makes the process a lot easier.

The aquarium needs minor preparations beforehand to receive the polyurethane:
- stick small offcuts of glass, at intervals of a few centimeters, in the places that will hold the decor;
- another option is to make a mixture of sand and silicone glue and deposit this mixture at regular intervals in the areas to be decorated.

Then pour on the polyurethane in small doses. You can work vertically to create a decor resembling a cliff; it is also possible to incorporate rocks, pieces of dead coral, or cavities for plants. In tanks equipped with a box filter, do not forget the passageways for the water coming in and going out; these can be molded on plastic pipes. The polyurethane dries very quickly and can be sculpted with a knife or small saw, to give it a finish that is more natural than its original smooth surface. Finally, use a vacuum cleaner to remove the off cuts.


Natural or Artificial? In reality, this saltwater aquarium decor is a mixture of the two, colonized by invertebrates.

Terracotta
Terracotta decors, made from clay to imitate the form of rocks, are commercially available from specialist suppliers. Although some hobbyists make their own terracotta decor, polystyrene and polyurethane are more common, largely as a result of aquarium clubs and associations that offer guidance to beginners in these techniques.

• Making a terracotta decor
Contact a tile or flowerpot factory to obtain the raw material and to get it fired. Use clay, which is neutral and malleable. For a medium-sized decor, calculate around 100 g of clay per liter of volume, but only practice or the advice of more experienced aquarists will offer you more precise indications.

Model the clay in accordance with the decor you want:
- rocks of varying sizes;
- rocky cliff or slope;
- grottoes, arches.

The end results should have a natural look. All the elements must be dried in the open air and then fired in an oven at 800-900°C. This reduces their weight by 25-30% and endows them with a color resembling tiles. A final option is the application of resin and sand on the surfaces of the decor.

Resin

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Resin applied to polyurethane can be dyed with food colorings, in this case a mixture of red and black.

This allows you to polish the decor. It is possible just to use artificial decor without treating it and wait until it acquires a patina after being in the tank for a few months. However, most hobbyists prefer to give it a natural appearance by incorporating a range of materials: sediments of varying textures, such as sand, gravel, coralline sand, or pieces of rock or coral.

To make these adjustments, a so-called food resin, epoxy resin, is used, as it has no influence on the water. It is made up of two components which harden when they are mixed together, and it can be colored to look more natural.

Finishing Artificial Decoration: Resin and Sand
Resin and sand completely insulate the decor from the water and give it a natural look. The sand used must be in keeping with the type of aquarium - freshwater or marine - and match the sediment. If you use fine sand, you will need to apply several layers.

• Polystyrene or terracotta decor
The resin and sand are added outside the aquarium. A coat of resin is applied with a paintbrush and sand is then sprinkled on top. Leave to dry (24 hours for the layer of resin) and repeat the operation 1-3 times, depending on the sand's grain size.
It is important to apply the resin carefully over all the decor, without neglecting any small reliefs, crevices, or grottoes. Only resin, without any sand, should be put on those parts of the decor that will be touching the glass panes of the aquarium.
Remove any leftover sand, firstly with a large paintbrush, and then with a vacuum cleaner. The finished decor is stuck to the aquarium with silicone glue, 48 hours after drying.

• Polyurethane decor
Follow the same process with the polyurethane set in the aquarium, and do not forget to apply resin and sand to the joins between the decor and the glass panes. Any leftover sand is removed with a vacuum cleaner.

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External Decoration
At first sight, it may seem surprising to talk of external decor. However, there is nothing more unsightly than the sight of the wall behind the aquarium covered with cables and pipes! The primary role of external decor therefore consists of masking these elements, but it can also serve to highlight the plants and fish.

• Posters
Posters with various designs, representing freshwater vegetation or sea beds, can be found in aquarium stores, but many aquarists remain unimpressed by their visual effect. They are attached to the outer face of the rear pane.

• Colored backgrounds
An alternative to posters is sheets in a single color, such as blue, green, gray, pale brown, or black. Black highlights fish and plants particularly effectively. A few aquarists paint a color scale themselves, pale at the top of the aquarium and darker at the bottom, to simulate the penetration of the light. Another option is to paint directly onto the back of the rear pane.

• Mirrors
Always placed behind the rear pane, these give the impression that the tank is twice its initial size... but also that is has double the number of plants and fish!

• Other possibilities
A polystyrene sheet with a coat of resin and sand can be placed against the outside of the rear pane. Finally, you can consider putting natural decorative material, such as rocks, branches, and roots, behind the aquarium, in front of a black cardboard backdrop. These elements can be simply wedged together, glued, or held down with adhesive clay. The overall effect is to increase the depth of field, for when an aquarium is full it seems one third smaller, because of the refraction of light in the water. This type of decor can easily be changed, needs no prior treatment and very little maintenance, the only is advantage being that it accumulates dust.

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