General Hardness (GH) and Carbonate Hardness (KH) are measures of mineral content in aquarium water, specifically calcium and magnesium for GH, and carbonates and bicarbonates for KH. Elevated levels can create an unsuitable environment for certain fish and plants, hindering their growth and overall health. Maintaining appropriate GH and KH values is crucial for a thriving aquatic ecosystem.
Controlling mineral content is important for several reasons. Some fish species originate from soft water environments and cannot tolerate high GH. Similarly, excessively high KH can make pH management difficult, leading to instability and stress for aquatic life.