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Aquarium Thermometers & Fish Tank Thermometers, Refractometers & Hydrometers

Thermometers
American Marine Pinpoint Wireless Aquarium Thermometer System
Digital read out of aquarium temperatures. One monitor can read up to 4 separate readings by utilizing additional sensors.
Coralife Digital Thermometer
Readings in 0.1 degrees Fahrenheit or Celsius. Temperature range -10 degrees F to 140 degrees F (-23 degrees C to 60 degrees C).
Hagen Floating, Standing, Stainless, Aquarius & Nova Thermometers
A wide variety of thermometers to choose from. Inexpensive, accurate and easy to read.
Hydra Aquatics Thermometers
Designed to hang on to the walls of rimless glass tanks 3-8mm thick. Reliable, easy to read and measure temperatures ranging 30-100 degress Fahrenheit. The minimal design allows aquarium keepers to place the thermometers inside their tanks without obstructing views.
JBJ Digi-Temp Thermometer
Digi-Temp is perfect for Nano Cubes that demands compact size with pinpoint accuracy.
Lifegard Aquatics Digital Thermometers
Little Time & Temp Digital clock/thermometer with light & the Big Digital Temp Alert Thermometer with large face digital thermometer with alert features.
Refractometers / Hydrometer
American Marine PinPoint Electronic Salinity Monitor
PINPOINT Salinity Monitor™ will accurately and immediately measure the amount of salt in any marine or freshwater system. The accuracy is superb!
Coralife Deep Six Hydrometer
The unique design allows hobbyists to take water samples at six inches in depth without submerging their hands in the water, thus avoiding the possibility of contamination.
Hagen Hydrometer
Accurate and easy to read floating hydrometer and thermometer all in one.
Hanna Instruments Digital Seawater Refractometer
A rugged portable, water resistant device that utilizes the measurement of the refractive index to determine the salinity of natural and artificial seawater, ocean water or brackish intermediates.
Milwaukee Seawater Digital Refractometer
Simple and easy to use! Samples are measured after a simple user calibration with distilled or deionized water. Within seconds, the refractive index and temperature are measured. Temperature is also displayed on the large dual-level display.
Red Sea Hydrometer with Digital Thermometer
Unique intergrated hydrometer and thermometer. Patented design enables device to be permanently installed inside aquarium, allowing time for micro bubbles to dissolve for continuous, accurate, real-time reading of salinity in addition to regular periodic reading.
Refractometers
The most accurate way to test your aquariums' specific gravity. An absolute must for the marine hobbyist, we offer 4 different models so you can choose the right model at the right cost.
SeaTest Hydrometer
Improved design delivers precise salinity and specific gravity readings. Easy-fill keep hands dry when filling. Durable and easy-read 2-color scale and an extra-wide base.
Salinity is a measure of the concentration of dissolved salts in water. Normal seawater tends to run in the range of 1.021 to 1.025 with the Red Sea area having a slightly higher level of up to 1.027. Salinity can be measured in a marine or reef aquarium a hydrometer or refractometer.

Hydrometers are easy-to-use devices that give readings in specific gravity and/or salinity. It is recommended that you first calibrate a hydrometer with a refractometer or salinity monitor before usage. Refractometers are much more accurate and are also very easy-to-use.

Fish tank or aquarium thermometers are an extremely important item for any aquatic habitat. Monitoring temperatures for better control and stability will aid in the overall health of your animals. There are many different types of thermometers to choose from, including digital (battery operated), glass and liquid crystal stick-on.

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