This salinity refractometer should be used to measure artificial seawater in aquariums, holding tanks and breeding ponds. REED R9600 Offers This salinity (salt) refractometer shows the concentration (percentage) of dissolved salt in water with 2 to 3 drops of a sample. The R9600 can be used to verify and measure salt concentrations in aquariums, holding tanks and breeding ponds. Features Measures the concentration of dissolved salt in water (0 to 28% Salinity) Easy to operate with simple to read scales Requires only 2 or 3 drops of sample Automatic Temperature Compensation (ATC) Prism and lens with a simple focus adjustment provides repeatable results Included Refractometer Cover plate Calibration screwdriver Cleaning cloth Solution/Sample applicator Hard carrying case