KH (OR CARBONATE HARDNESS)
KH measures the amount of carbonates and bicarbonates in water, which affects the buffering capacity of the water. This means that KH helps neutralize acids and prevents your pH from changing too rapidly, which is useful because sudden pH crashes can cause health issues in your fish. Low KH means your water has less buffering capacity and the pH swings easily. High KH means your water has more buffering capacity and the pH level is hard to change.
Think of KH like a trash can. The higher the KH, the larger the trash can. If we overflow that trash can, then a pH crash occurs. Therefore, people with low KH in their tap water often use BIOTOPE KH Balance to gradually raise the KH (or increase the size of their trash can) and prevent pH crashes.
KH is measured in dKH (degrees of KH) or ppm (parts per million), where 1 dKH equals 17.9 ppm. Typically, freshwater aquariums should be between 4-8 dKH (or 70-140 ppm). If you need to lower the pH for animals like discus or crystal shrimp, you’ll need to decrease the KH to 0-3 dKH (or 0-50 ppm). African cichlids, on the other hand, appreciate KH higher than 10 dKH (or 180 ppm), which usually goes hand in hand with higher pH levels.
