The substrate of the aquarium

The Substrate

The substrate performs vital functions in the ecosystem formed in the aquarium. It is the livelihood of plants and can give shelter to fish. It inhabits bacteria essential for the development of the system. These bacteria are responsible for decomposing waste and converting it into nutrients.

Mineral and organic nutrients are housed in the substrate that will be used by the plants. Bacteria fulfill the function of reducing the already mentioned nutrients so that they can be absorbed by plants. Some nutrients such as iron cannot be taken by plants if they are not reduced.

The reduction consists in transforming the iron oxide (Fe + 3) into Fe + 2. The difference is that after iron is reduced, the negative areas at the bottom attract positive ions and retain them until the plants take them by their roots.

Bacteria decompose plant and fish waste. Also unconsumed food. When setting up a new aquarium, it is necessary to allow time for bacteria colonies to form, before introducing fish or plants.

It is most suitable to use gravel from a stable aquarium in full operation. It is also valid to buy bacterial cultures in specialized stores to avoid virgin aquarium syndrome, which could kill fish by high levels of ammonia in water (see nitrogen cycle).

The Substrate Cycle

Gravel must be washed before being put into the fish tank. NEVER use any soap or detergent. Since although before our eyes it seems that it is easily rinsed, a very thin layer is always adhered to. This would destroy any kind of life present in the aquarium.

Until bacteria colonize the aquarium plus ammonia and nitrites levels in the water are acceptable for fish life, a period of not less than one month elapses. After the first week the plantscan be incorporated, so that between the bacteria and them a balance in the wateris achieved.

It is substrate compacts over time. Very moderate siphoning of the bottom with a clean gravel tube will help keep it cleaner. It will have to be done with sufficient care so as not to alter the action of fertilizers for plants.

Below are described the main characteristics of gravel available for aquariums. Filtration sand, laterite or clays can also be used for planted aquariums. A good idea is used gravel supplemented by red clay. The clay should be placed under the gravel, so that it is not necessary to remove it in the siphoning process.

Standard Gravel

Small stones are always well rounded, which prevents injuries to fish looking for food at the bottom, and even fish like Kuhli that have as a habit to bury themselves under these pebbles.

Fine Gravel

Try to get dark fine gravel to avoid the inconvenience described above. There is black quartz gravel that gives a very interesting effect aesthetically to the bottom of the aquarium.

Red Gravel

Food that reaches the bottom without being consumed by fish will be placed between the pebbles. Because they are not hit by bottom fish, these remains of food rot and pollute the water. Even your aquarium will smell bad for this very reason.

Filtration Sand

It is also characterized by being less compact, which allows the passage of water in the biological filtration and allows the roots of plants to expand without difficulty.

© Adrián Blanco 2005/2006 — No full or partial reproduction of text and/or images without explicit written consent of the author.

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