10 Best Hydrometer For Saltwater Tank of August 2025

• Included components: All Components included in Picture and Description
• Cora life is one of the markets leading manufacturers of premium aquarium products
• Cora life's Hydrometer takes a true water sample at six inch depth
• Easy to read and accurate, this specific gravity meter is designed to give temperature-corrected readings in warm water aquariums
• Coralife is one of the market’s leading manufacturers of premium aquarium products
• Coralife's Hydrometer takes a true water sample at six inch depth

Coralife

• Measure salt water or salinity of water, ideal for aquariums and marine monitoring.
• Measures on 2 scales, Specific Gravity (D 20/20) and parts per thousand.
• Features automatic temperature compensation.
• Comes with hard case, dropper, screwdriver, user manual and cleaning cloth.
• The main part is made of chromium, it's very durable.

Agriculture Solutions

• 【Salinity Refractometer】Measure Salt Water or Salinity of Water,Monitor and Control the Concentration of Salt Water and Brine,Ideal for Aquariums and Marine Applications.
• 【Measures on 2 Scales】Specific Gravity (D 20/20) and parts per thousand and replaces your poor quality and difficult to read hydrometer.
• 【Density Measurement Range】1.0-1.070, Minimum Scale is 0.001.
• 【Concentration Measurement Range】0-100‰, Minimum Scale is 1‰.
• 【ATC】Automatic Temperature Compensation, 0-10°C.

AUTOUTLET

• ⭐️ DUAL SCALE REFRACTOMETER: Measures in Salinity 0 - 100ppt and Specific Gravity 1.000 - 1.070
• ⭐️ IDEAL APPLICATIONS: Aquariums, Marine Monitoring, Agricultural, Gardening & Educational Purposes (Biology Projects)
• ⭐️ AUTOMATIC TEMPERATURE COMPENSATION (ATC): Automated to provide accurate measurements even with temperature fluctuations
• ⭐️ AFFORDABLE high quality while providing ⭐️ PROFESSIONAL testing equipment standards, accurate even at low salt levels
• ⭐️ STANDARD PACKAGE INCLUDES: 1 Refractometer, 1 Hard Carrying Case, 1 Calibrating Screw Driver, 1 Pippet, 1 Cleaning Clothe, 1 Instruction Manual

AquaticHI

• Ensures proper gravity of aquarium water. Easy to use.
• Ensures all water has the same salinity within aquarium
• Green indicators are ideal range of water temperature and specific gravity for most salt water / marine aquariums.
• Measure both Temperature and Specific Gravity of the water.
• SIZE：19.2CM(7.5"). Glass Hydrometer; Measures Celsius and Fahrenheit

Aquarium Equip

• 🐠 Safe Material & Unique Design: Made of durable Acrylic, this Fish Tank Test Kit salinity Hydrometer is designed with an automatic level function.
• 🐠 Quickly, easily, and accurately measurement: With this hydrometer saltwater aquarium test kit, you can test your marine aquarium's salt level and specific gravity, and It is optimum to be put into below 6" deep water to avoid the error caused by the oil film on the water.
• 🐠 Higher Accuracy & safe zone indicated: Readings are temperature-corrected & accurate to +/- 0. 001. specific gravity units ranges from 1. 000 - 1. 030 with a safe zone of 1.020-1.023. The outside range of scale indicates salinity ppt, ranges from 0-40, safe zone is 27-31.
• 🐠Easy to Read & Clean: The easy-to-read swing-arm pointer and extra wide stable base provide an accurate test result. After use, soak this saltwater meter in mild acid(vinegar) for 30 minutes, rinse with tap water and air dry. Do not disassemble.
• 🐠 Wide Usage:Fit for brackish and reef salt marine aquariums. Perfect for testing both salinity and specific gravity of your brackish and marine tank.Includes salinity and specific gravity scales.Suitable for fresh water and sea water.

capetsma

• Measures on 2 Scales: Aquariums refractometer features Specific Gravity (D 20/20) 1.000-1.070sg and parts per thousand 0-100PPT (1‰=1ppt=1000ppm)
• Seawater refractometer measures saltwater or salinity of water, ideal for aquarium, marine monitoring, fish-keeping,salty pools&spas and etc.
• ATC Function: salty water refractometer with automatic temperature compensation, allow you obtain accurate readings easier and faster
• Salinity Refractometer is made of aluminum body and ABS rubber light and very sturdy, comes with a hard plastic case, a mini screwdriver, a dropper
• Easy to Use: put 2-3 drops on the saltwater’s prism, towards light then to get the accurate readings through the optic eyepiece, ideal for replacement the poor quality and difficult to read hydrometer refractometer

RZ

• ❤DUAL SCALE: Measuring Ranges: 0-100 ppt of Salinity and 1.000 to 1.070 Specific Gravity (0-10%)the reading resolution is 0.1 %. Salinity Accuracy: +/-0.1%
• ❤APPLICATIONS: Aquariums, Marine Monitoring, Agricultural, Gardening & Educational Purposes (Biology Projects)
• ❤EASY TO USE:Automatic Temperature Compensation (ATC),Just need 2-3 drops of solution,you will be able to read accurately the result
• ❤PORTABLE AND DURABLE: Made with non-staining, non-corrosive and non-reactive aluminum material, light-weighted and portable, safe and durable
• ❤PACKAGE INCLUDES: 1 Refractometer, 1 Carrying Case, 1 Calibrating Screw Driver, 2 Pippets, 1 Cleaning Clothe, 1 Instruction Manual

Hobein

• Performance driven at affordable prices
• Made in the USA with quality materials
• Field tested to ensure nothing but the best for your pet
• Item Package Weight: 0.185

Fluval

• 🐠Safe Material:Made of plastic,aquarium clear Automatic Accurate Readable SaltWater Hydrometer.
• 🐠Durable Clear Acrylic:Accurate, durable, and easy to read your marine aquarium's salt level and specific gravity,Small and waterproof.if the specific gravity between 1.000 - 1.019,show that the specific gravity is small;if the specific gravity between 1.020 - 1.023,show that the specific gravity is nomal;if the specific gravity between 1.024 - 1.030,show that the specific gravity is big;
• 🐠Clearly Safe Zone Indicated:Includes solinity and specific grovity scales.The outside rang of scale indicates salinity(PPT).The inside range of scale indicates gravity.And with safe zone clearly indicated.Range of use: 0-40 degrees (1.000-1.030).If the salinity ppt between 32 - 40，show that the salinity hydrometer is high;If the salinity ppt between 27 - 31，show that the salinity hydrometer is normal; If the salinity ppt between 0 - 26，show that the salinity hydrometer is light.
• 🐠Wide Usage:Fit for brackish and marine aquariums.Perfect for testing both salinity and specific gravity of your brackish and marine tank.Includes solinity and specific grovity scales.Suitable for fresh water and sea water.
• 🐠Easy to Read and Use:The easy-to-read swing-arm pointer and extra wide stable base provide an accurate test result.

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