A MUST HAVE FOR DEDICATED REEF KEEPERS The KHG is an all-in-one device that automatically monitors and manages carbonate hardness values throughout the day. Such an instrument is often considered "the holy grail" and can dramatically simplify and improve the way we manage KH parameters of a reef tank. Test accuracy is +/- 0.1dKH Automatic tests carbonate hardness levels directly from aquarium Controls your KH values throughout the day resulting in rock-solid stability Continuous monitoring and data logged Onboard memory for the long-term data logging Easy to read LED display Compact, easy installation and simple operation Bio-Safe reagent can be dosed back into the aquarium No software or APP required* Dimensions: 7.75″ long x 5″ wide x 9.75″ high *The KHG does require a home network to opperate