WATER, A HAVEN FOR LIFE TURBIDITY Clarity is more important in sea water than in fresh water. Tropical environments in particular contain very few dissolved solids and they are the most transparent waters on the planet. A marine aquarium must therefore be filtered more efficiently and to a greater extent than a freshwater tank (see […]
FINDING OUT THE CHARACTERISTICS OF NATURAL WATER The European Union has set compulsory standards for drinking and environmental quality, but the strict legislation in the UK goes well beyond these. In England and Wales, for example, domestic water is monitored by the Drinking Water Inspectorate, which regularly checks up on the practices of the water […]
THE NITROGEN CYCLE This occurs in the same way in sea water and fresh water. In a marine aquarium the vegetation is often less abundant than in fresh water, and so the nitrates, the end products of the nitrogen cycle, will have a tendency to accumulate. At high doses these pose little danger to fish […]
MEASURING DENSITY Density is measured with a hydrometer, whose buoyancy increases as the water gets saltier. In the aquarium trade, most hydrometers also include a thermometer. The specific gravity at water level must be read with care; in fact, it is preferable to use the hydrometer outside the aquarium, as the movement of the water […]
In marine aquariums, it is not the salinity of water which is measured, but the density (often expressed as specific gravity, S.G.), which can be calculated according to the following formula:There are no units of measurements. The saltier the water, the higher its density. The density also varies according to temperature (it goes down as […]
The main difference between fresh water and sea water is that the latter contains a great many salts which give it certain specific characteristics, and these must be understood by any aquarist who wishes to keep marine fish.TEMPERATURE The temperature of tropical sea water varies little over the course of a day, or even a […]
Rainwater is soft and acid, so is useful for diluting water that is too hard. It should be collected in plastic containers; if these are put under a gutter, take care not to collect the first water, as this will have cleaned the roof. In urban and industrial areas, rainwater is liable to contain pollutants, […]
OTHER DISSOLVED SOLIDS A great many other substances are to be found dissolved in water. Their content is generally low and does not pose any problems, and some of them, such as micronutrients, are even very beneficial. This term covers a variety of elements including vitamins and metals, which in tiny quantities are indispensable to […]