Description

This model also includes a SG (specific gravity) scale and is perfect for measuring the salinity of marine aquariums.
A refractometer is a valuable tool for accurately determining salt content, surpassing a hydrometer in precision. The ppt (parts per thousand) and SG scales allow for effortless monitoring of your tank’s salinity, ensuring healthy fish. Divisions on the ppt scale indicate increments of 1 ppt, while the SG scale features 0.001 increments. It is specifically designed for measuring salt density in sea water and boasts a sturdy, corrosion-resistant brass construction.
For easy and precise readings, it has a high-contrast demarcation line and an easily adjustable zero line with a readily accessible screw.

Getting Accurate Salinity Readings with the ANS Refractometer

For any marine or reef keeper, this refractometer is the tool we recommend over a swing-arm hydrometer, which drifts and reads erratically as bubbles cling to it. With the dual ppt and SG scales you simply place a drop of tank water on the prism, hold it to the light, and read the line directly. That precision matters when stocking sensitive corals and fish, where being off by a few points of salinity can stress livestock over time.

One step many local hobbyists skip is calibration. Temperature and storage affect the prism, so we zero ours against RO or distilled water before a measuring session, especially after a spell of sitting in a humid cabinet. A quick wipe of the glass between readings keeps salt residue from skewing the next sample. Treat it as a precision instrument and it will serve a tank for years.

Find salts, RO water and test kits in our water testing & care range. Our refractometer calibration guide and hydrometer vs refractometer comparison cover the details.