Keep your fish healthy and thriving by testing your aquarium waters KH levels regularly with this easy-to-use API CARBONATE TEST KIT for freshwater aquariums. API CARBONATE HARDNESS TEST KIT helps prevent pH problems by stabilizing aquarium pH in fresh and saltwater aquariums. Fast, easy, and accurate testing evaluates KH levels in aquarium water, so that they may be corrected if too low or high. Water with low KH is susceptible to rapid pH shifts, stressing fish and increasing the risk of disease. In marine aquariums, proper KH levels are necessary for healthy coral growth. Kit contains 1 KH test solution bottle, one instructional booklet, and one glass capped test tube. With API Aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For over 50 years, API has been creating innovative, research-driven solutions that make it easier to care for your fish and aquarium. API Aquarium Treatment Supplies are designed to work in conjunction with each other to provide best results to control algae, promote healthy bacterial growth and help control and cure fish diseases and conditions such as ich and fin rot. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. With API, you can spend more time admiring your fish, and less time scrubbing your tank. Make sure to use all products as directed in order to ensure the best results.