CarbonatAlkalinität

CarbonatAlkalinität, often abbreviated as CA or kH, is a measure of the water's buffering capacity against pH changes, specifically related to the concentration of carbonate and bicarbonate ions. It is a crucial parameter in aquatic environments, particularly in aquariums and natural water bodies like lakes and rivers. High carbonatalkalinität indicates that the water can resist significant fluctuations in pH, meaning it is more stable. Conversely, low carbonatalkalinität suggests the water is susceptible to rapid and potentially harmful pH shifts.

The primary contributors to carbonatalkalinität are dissolved carbon dioxide, carbonic acid, bicarbonate ions, and carbonate ions. These species are in equilibrium with each other and are influenced by the pH of the water. In freshwater systems, a typical range for healthy aquatic life is between 4 and 15 degrees of carbonate hardness (dKH), where 1 dKH is equivalent to approximately 17.86 mg/L of calcium carbonate. For marine aquariums, higher values, often in the range of 8 to 12 dKH, are generally preferred to support coral growth and the health of many invertebrates.

Maintaining appropriate carbonatalkalinität is essential for many biological processes, including photosynthesis by aquatic plants and the proper functioning of fish gills. Fluctuations in CA can stress aquatic organisms and lead to health problems. Therefore, regular testing and adjustment, if necessary, are common practices for aquarists and water managers.