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92 products
Red Sea Seawater Refractometer
Starting at $59.99
* Refractometer for measuring salinity of seawater for reef aquariums * Calibrated to measure absolute salinity of seawater, not brine (NaCl) * High resolution display focuses on the range relevant for reef aquariums Maintain proper salinity level with greater precision and convenience. Red Sea…
Milwaukee Instruments Seawater Digital Refractometer
Starting at $110
…setups.Milwaukee Instruments Seawater Digital Refractometer measures and displays temperature compensated results in Practical Salinity Units (PSU), Salinity in parts per thousand (ppt), or Specific Gravity (S.G. (20/20)). Professional optical instrument delivers the highest accuracy possible…
Instant Ocean Hydrometer
Starting at $9.49
…Precise full range salinity and specific gravity readings * Large easy-to-read pointer and wide stabilizer base Instant Ocean's durable, clear acrylic, swing-arm hydrometer is easy to use and easy to read. Full-range results in both salinity and specific gravity (0 to 40 ppt salinity and 1.000 to…
Neptune Systems AquaController Apex PM2 Salinity Module
Starting at $84.95
*Salinity probe module for all AquaController Apex controller systems*Expansion module provides conductivity & temperature probe ports*Monitor aquarium salinity in real-time from your computer or mobile deviceMonitor aquarium salinity in real-time with this simple upgrade to your AquaController Apex…
Pinpoint Salinity Monitor
Starting at $109.99
Salinity Monitor, the only truly accurate and affordable Salinity measurement system. A 9-volt battery should be used for intermittent or field use while a PINPOINT AC Adapter Kit can also be installed. Battery replacement is visually indicated on the display as "LOBAT."NOTE: The Salinity Monitor…
Brittle Sea Star, Red
(Ophiocoma sp.)
Starting at $13.99
…and small organisms. It cannot tolerate copper-based medications.The Red Brittle Sea Star is very intolerant of sudden changes in oxygen levels, salinity and pH of the water, and cannot tolerate copper-based medications. The drip acclimation method is highly recommended for all Sea Stars due to…
Upside Down Jellyfish
(Cassiopea sp.)
Starting at $12.99
…photosynthesis to occur. It will not tolerate copper or high nitrates in the water, and since its body is composed of 95 to 98% water, sudden changes in salinity or pH can have radical consequences.Its sting is mildly toxic; humans very rarely notice the sting. Care should still be taken though when…
Auto Top Off Controller
Starting at $79.99
*Automatically refills evaporated aquarium water*Maintains aquarium and sump water level to prevent pump damage*Save time and effort by automating aquarium top-offsAutomatically refill your sump or aquarium without lifting heavy buckets or spilling water. Floating sensors monitor water level and…
IceCap Salinity/Temperature Digital Pocket Tester
(LiveAquaria® Approved)
Starting at $79.99
*High-resolution salinity measurement*Automatic temperature compensation*Reads water temperature within seconds Get accurate temperature and salinity readings in seconds and eliminate the uncertainty associated with mechanical refractometers with the IceCap Salinity/Temperature Digital Pocket…
Linckia Sea Star, Blue
(Linckia laevigata)
Starting at $19.99
…will tolerate other starfish and amiable fish in the aquarium.The Blue Linckia Sea Star is very intolerant of sudden changes in oxygen levels, salinity and pH of the water, and cannot tolerate copper-based medications. The drip-acclimation method is highly recommended for all Sea Stars due to their…
Neptune Systems Lab Grade Salinity/Conductivity Probe
Starting at $124.95
*Lab Grade salinity probe for Neptune Systems aquarium controllers*Enjoy accurate results plus less frequent calibration & replacement*Essential measuring tool for salinity data supported Apex functionsLab grade salinity probe from Neptune Systems provides accurate water parameter measurement…
Deep Six Hydrometer
Starting at $6.99
…swing-arm hydrometer measures specific gravity and salinity * Improved calibration ensures more accurate reading of aquarium water * Temperature-corrected and accurate to ±0.001 specific gravity units Precision hydrometer tests both salinity and specific gravity accurately and without getting…
53.0 mS Calibration/Reference Fluid
Starting at $8.99
* Precision calibration solution for electronic salinity monitors * 53.0 mS standardized fluid provides accurate reference point * Can also be used as a reference solution for refractometers Calibration solution for Pinpoint Salinity Monitor. This 53.0 mS (milliseimens) standardized fluid from…
Portable Refractometer
Starting at $44.99
…device provides a direct reading of specific gravity and salinity in water. Requires no batteries and automatically compensates for temperature.Temperature Correction: Automatic from 50-86°F (10-30°C)Reading: Dual scale, 0-100 ppt salinity and 1.000-1.070 specific gravityWeight: 10 oz.Warranty:…
Two Little Fishies AccuraSea Seawater Reference Calibration Solution
Starting at $11.04
*Standardized reference solution for marine aquarium testing devices*Natural seawater at 53.0 mS (S 35) provides accurate reference point*Confirm accuracy of aquarium hydrometers, refractometers, & moreEnjoy greater accuracy from your saltwater testing devices when you check them against a…