API GH & KH Test KitThe API GH & KH Test Kit measures the two kinds of water hardness — general hardness (GH, the dissolved mineral content) and carbonate hardness (KH, the buffering capacity that stabilizes pH). These are the parameters that matter most for matching your water to your fish, plants, and especially shrimp, and for preventing the dangerous pH swings that a low KH allows.Good to Know: GH and KH are the unsung heroes of a stable tank — especially for shrimp keepers, where Neocaridina and Caridina want very specific hardness ranges, and for anyone building water from RO with a remineralizer. KH in particular is your safeguard against pH crashes. This liquid kit is more precise than strips, using a simple drop-count method (each drop = one degree of hardness).How to Use: Add tank water to the tube, then add the GH (or KH) reagent one drop at a time, counting drops and swirling until the color changes — the drop count gives your hardness. Test when setting up, mixing RO water, or keeping shrimp.
