1.Use this tool to accurately measure salinity in liquids. Refractometers measure how much light bends, or refracts, when it enters the liquid. This is called the refractive index. The more salts (and other material) dissolved in the water, the more resistance the light will meet and the more it will bend. This is because light travels at different velocities depending on the medium.
Note: If you have not yet used your refractometer, you may wish to calibrate it first for a more accurate reading. This process is explained at the end of this section, but you may wish to read the following steps first so you are more familiar with how to work the device.
2.Select a refractometer designed for the liquid you wish to measure. Different liquids already refract light by different amounts, so to accurately measure additional salinity (or other solids content), use a refractometer designed specifically for the liquid you intend to measure. If the liquid is not specifically mentioned on the packaging, the refractometer is probably designed to measure salt water.
Note: Salt refractometers are used to measure sodium chloride dissolved in water. Seawater refractometers are used to measure the mixture of salts typically found in seawater or saltwater aquariums. Using the wrong one may result in a reading approximately 5% off, which may be acceptable for non-laboratory purposes.[2]Refractometers are also designed to compensate for the expansion of a specific material due to temperature changes.[3]
3.Open the plate near the angled end of the refractometer. A handheld refractometer has one round, open end to look through, and one angled end. Hold the refractometer so the angled surface is on the top of the device, and find the small plate near this end which can be moved to one side.
Note: If you have not yet used your refractometer, you may wish to calibrate it first for a more accurate reading. This process is explained at the end of this section, but you may wish to read the following steps first so you are more familiar with how to work the device.
Answers & Comments
1.Use this tool to accurately measure salinity in liquids. Refractometers measure how much light bends, or refracts, when it enters the liquid. This is called the refractive index. The more salts (and other material) dissolved in the water, the more resistance the light will meet and the more it will bend. This is because light travels at different velocities depending on the medium.
2.Select a refractometer designed for the liquid you wish to measure. Different liquids already refract light by different amounts, so to accurately measure additional salinity (or other solids content), use a refractometer designed specifically for the liquid you intend to measure. If the liquid is not specifically mentioned on the packaging, the refractometer is probably designed to measure salt water.
3.Open the plate near the angled end of the refractometer. A handheld refractometer has one round, open end to look through, and one angled end. Hold the refractometer so the angled surface is on the top of the device, and find the small plate near this end which can be moved to one side.