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Aquarium Hydrometers & Refractometers

How to use a hydrometer
A swing arm hydrometer offers basic salinity testing. Simply place tank water in the hydrometer and the arm will point to the salinity level. Reef salinity is typically between 1.024 and 1.026 specific gravity.

How to use a refractometer
A salinity refractometer is a more advanced way of measuring salt levels. Place a few drops of water under the plate, point the refractometer at a light source and look through the eyepiece. A shift in color will indicate the specific gravity. Be sure to use a seawater refractometer with automatic temperature compensation.

Refractometer vs hydrometer
We recommend a refractometer because hobby level hydrometers lack precision.
13 Results
Hanna Instruments Salinity Tester (HI98319)

Hanna Instruments Salinity Tester (HI98319)

Marine Depot Aquarium Refractometer

Marine Depot Aquarium Refractometer

Hanna Reef Test Kit (HIREEF2) - Hanna Instruments

Hanna Reef Test Kit (HIREEF2) - Hanna Instruments

Milwaukee Seawater Digital Refractometer

Milwaukee Seawater Digital Refractometer

IceCap Salinity/Temperature Digital Pocket Tester

IceCap Salinity/Temperature Digital Pocket Tester

AquaMaxx REEFractometer Refractometer

AquaMaxx REEFractometer Refractometer

Red Sea Refractometer

Red Sea Refractometer

Milwaukee Seawater Digital Refractometer with Protective Hardshell Case

Milwaukee Seawater Digital Refractometer with Protective Hardshell Case

Hanna Instruments Digital Seawater Refractometer

Hanna Instruments Digital Seawater Refractometer

Coralife Deep Six Hydrometer Wide Range Specific Gravity Meter

Coralife Deep Six Hydrometer Wide Range Specific Gravity Meter

Fluval Sea Hydrometer

Fluval Sea Hydrometer

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