Labnox ORP Liquid is a great way to test water , conductivity and ORP. Just add one drop per gallon of water. ORP (Oxidation Reduction Potential) is a measure of the electrical potential between two electrodes in water. Water orp testing reagent liquid suitable for testing tap, Ground and RO Water. Place a few drops of the orp liquid to test your tap or drinking water orp level. Check results instantly with the color. If color is pink orp is negative reading and if color remains trasparent then orp is positive reading. This solution is used for orp measurement of swimming pools, larger pools, aquarium water, ro water purifier and water quality testing. When the ORP value is high or higher orp solution, there is lots of oxygen present in the water. This means that bacteria that decompose dead tissue and contaminants can work more efficiently.