Note: Before using for the first time, to season the measurement needle, fill the hydrometer with saltwater from your aquarium and allow it to sit full of this water on a level surface for 24 hours. This rehydrates the calibration disc to its original specs and calibration standard and will provide the most accurate readings going forward.
- Submerge hydrometer approximately 6 inches to water level line.
- When water reaches the fill line level (top of dam) remove hydrometer and place on a level surface to take the most accurate reading.
- Avoid air bubble adherence to the pointer as this will result in inaccurate, higher than normal readings. Should air bubbles collect on pointer, gently tap hydrometer to dislodge them before taking your reading.
- Read specific gravity on inside scale and salinity in parts per thousand (PPT) on the outside scale. A recommended specific gravity of 1.020 to 1.023 is desirable for most marine aquariums.
- Rinse with fresh water after each use to maintain optimum accuracy.
Salt deposits may accumulate on pointer and will result in inaccurate readings. If salt crystallizes inside your unit, soak it in lukewarm water or vinegar for 30 minutes, rinse with fresh water and allow to air dry. Rinse again with warm fresh water before next use.
Each AccuProbe® Hydrometer is assigned an individual certified calibration number which is your assurance the unit was finely tuned prior to shipping from our production facility to provide the most accurate reading possible.
