The API® KH TEST KIT tests fresh or saltwater aquariums for carbonate hardness (KH), and helps monitor water quality and prevent invisible water problems that can be harmful to fish and plants. Carbonate hardness stabilizes aquarium pH, and can be used to determine the proper dose of pH buffers.

Contains 1 test bottle, easy-to-ready instructions, glass test tube and color chart

In stock

SKU: AQ3028 Categories: , ,
  • What is Carbonate Hardness (KH)?

Carbonate hardness, also known as alkalinity, is the measure of carbonate and bicarbonate concentrations dissolved in water. These minerals are present in municipal, well, and bottled water. The level of carbonate hardness in tap and bottled water depends on the source of the water and the treatment processes it has undergone. Carbonate hardness helps stabilize pH in the aquarium. An aquarium with a low KH level will tend to be acidic. Aquariums with very low KH are subject to rapid pH shifts if not monitored carefully. Water with a high KH level usually has a high pH.

Manual download