article: The aquarium water
Among the components of the aquarium, water is the most important. The water commonly used for freshwater aquariums comes from drinking water pipes and is a "quality" fit for human consumption more than to maintain the fish. The "quality" drinking water can vary according to different areas of collecting. Most of the fish adapt very quickly to the town water and only if you take very specialized species is necessary to consider the detailed examination of the composition of the water. There are two major indices of the water which are: the pH and DH or, in other words the degree of acidity or alkalinity of the water (pH), and the fact that it is "hard" ie limestone, or or "soft "or" soft "ie, non-calcareous (DH). The extension of the pH is calculated lagaritmicamente from 0 (the acidity stronger) to 14 (the alkalinity stronger), with a neutral point (neither acidic nor alkaline) to 7. In a freshwater aquarium water must be understood only in limited values of this scale, from approximately 6.5 to 7.5, while the pH of the aquarium of marine water is between approximately 7, 8 and 8.5. In an aquarium are likely to fish from the waters of both types. Hardness is due to dissolved salts in water, some can be eliminated by boiling (hardness), others do not. There are indicators to determine the factors that may affect the hardness of the hardness "General" or the "specific" produced by the presence of calcium carbonate (CaCO3), or calcium oxide (CaO). There are several units of hardness in ppm (parts per million), DH ° (German degrees) or hardness (Clark's level). When the hardness is expressed in ppm, it is generally accepted that refers to the hardness due to calcium carbonate, and the hardness of the "general". It can lower the water hardness by joining a given quantity of water more tender, that is, distilled water or rain water, or, according to a more sophisticated method, using resins which make the water less limestone. You might think that the hardness is a problem, but it is not, and there are many fish species including viviparous, and brightly colored cichlids of African lakes.
The water for the aquarium "sea" is easily prepared with a lot of mixes on the market, and it is better to use synthetic seawater. An important factor for those who have a marine aquarium is its density (the density is comparable units) that indicates the strength of the mixture of salt water and can be measured with a hydrometer. The specific gravity of a saltwater aquarium is generally between 1.020 and 1.025; instructions imprinted on the packaging of the mixture of salts are always very clear. After checking the specific gravity, the aquarium is not yet ready for the immediate release of the fish now must resort to another detector, this time for nitrites, to find out if these toxic substances have been transformed in the most harmless nitrates and only then can easily be introduced into the aquarium fish and other marine organisms.
An easy way to keep the water healthy, with low levels of waste products and toxic substances dissolved in water, is to follow a program of regular partial water changes, about twenty percent every two to three weeks 'freshwater aquarium, a greater extent, and perhaps with more frequent changes to the marine aquarium. It 'important that the water of substitution introduced is always of the same quality and at the same temperature than that which is removed. The decrease in marine water by evaporation must be supplemented with fresh water, never salt water to evaporation because the salts are not lost but remain in the aquarium.
The aquarium water
