API GH/KH General & Hardness Test Kit Fresh water

Product details

API GH/KH General & Hardness Test Kit Fresh water is a freshwater water testing kit designed to measure two key hardness parameters: carbonate hardness (KH/alkalinity) and general hardness (GH). In practical aquarium use, KH helps help stabilize pH by reflecting carbonate and bicarbonate levels, while GH reflects calcium and magnesium. Use this kit when you need to check water hardness for routine monitoring or when troubleshooting pH stability and mineral balance in your aquarium.

Features:

• Tests carbonate hardness (KH/alkalinity) and general hardness (GH) for freshwater aquarium water
• Uses a small 5 ml water sample for each test, making it convenient for regular checks
• Employs a drop-by-drop reagent method with clear visual color changes at the endpoint
• Includes conversion guidance for German degrees to ppm values (multiply °dKH or °dGH by 17.9)
• Helps avoid contamination risks by keeping test solutions away from the aquarium
• Features a clear endpoint approach: KH turns bright yellow, while GH turns from orange to green after shaking

Specifications:

• Test sample size: 5 ml of aquarium water (filled to the line on the test tube)
• Carbonate Hardness (KH) endpoint: Blue changes to yellow after shaking; each drop equals 1 °dKH or 17.9 ppm KH
• General Hardness (GH) endpoint: Orange changes to green after shaking; each drop equals 1 °dGH or 17.9 ppm GH
• What KH measures: Carbonate (CO3-) and bicarbonate (HCO3-) ion concentrations
• What GH measures: Calcium (Ca2+) and magnesium (Mg2+) ion concentrations