Editor's Choice - Our Favorite Digital Aquarium Hydrometers

1. GXSTWU Reptile Hygrometer Thermometer LCD Display Digital Reptile Tank Hygrometer Thermometer with H...

User Ratings: 71 5

GXSTWU HY-2 First Impressions

"Couldn't be happier."

I compared the readings using this hygrometer and the calibrated refractometer. But with alittle persistance I am able to read it. Not sure how accurate it is, but it's a good reference point. There are conversion charts and tables online. I will get one later but for now this will do, since im just starting. So once your instant ocean shows a measurement. Find a good light source to make reading easier.

  • GXSTWU Reptile Hygrometer Thermometer LCD Display Digital Reptile Tank Hygrometer Thermometer with Hook Temperature Humidity Meter Gauge for Reptile Tanks, Terrariums, Vivarium
  • 100% Brand New and High-Quality Reptile Tank Thermometer Hygrometer: Precise supervision of the temperature and air humidity in terrariums, vivariums and reptile tanks.
  • Stylish Design: Stylish looking digital vivarum thermometer with hook and loop for easy to install to any reptile tanks or terrariums. Comes with a battery so you can use the thermometer immediately.
  • Fantastic Value: This accurate reptile thermometer and hygrometer allows you to monitor the temperature and humidity in the reptile tanks at all times to makesure your beloved reptiles are in perfect health.
  • Fahrenheit Celsius Convertible: Temperature can be display in Fahrenheit or Celsius by press the C/F hole on the back of the item with a paper clip.
  • Quality Guaranteed: Our carefully sourced range of thermometer hygrometers are manufactured to the highest of standards our customers expect. And provide 365 days warranty, in case of any quality problems, please feel free to contact us by email, we will give you a satisfactory solution.
  • Manufacture: Cangda Electronics Co., Ltd.
  • Product Dimensions: 2.09 x 0.67 x 1.3 inches; 0.92 Ounces
  • Batteries: 1 LR44 batteries required. (included)
  • Editor's Impressions Of The GXSTWU HY-2
  • Accuracy [star rating='4.7']
  • Quality [star rating='4.7']
  • Value For Money [star rating='3.5']
  • Affordability [star rating='4.8']

GXSTWU HY-2 Final Thoughts

"Seems pretty solid."

Hate the batteries, but once loaded, it seems to work fine. If you let it sit in the tank overnight, it definitely gives an accurate reading. Like that it comes with everything needed. Get precise salinity readings in moments. I have to recalibrate it ever use though which worries me sometimes. This one read perfect, and the others were completely inaccurate. Plus it is super easy to use and clean.

Overall Score
4.4

[star rating="4.4"]
(265 Points)

Peoples Choice - Other Highly Rated Digital Aquarium Hydrometers

2. Eyourlife Salinity Refractomer Aquarium Optical Optics Refractometer with Auto Temperature Compensat...

User Ratings: 64 8

Eyourlife First Impressions

"So easy to use."

Great tool if you have a salt-water fish tank or a decorative pond. Ultimately, the measurement was exactly the same as our old tester. I have purchased before will buy again! Great product I used for beer making and my saltwater aquarium. I would suggest purchasing the salt calibration solution. I tried it over and over and no bubbles! Very quick to calibrate and to use.

  • Eyourlife Salinity Refractomer Aquarium Optical Optics Refractometer with Auto Temperature Compensation ATC Digital Dual Scale Salinity Meter Hydrometer Specific Gravity for Saltwater Seawater Marine
  • SALINITY REFRACTOMETER for measuring the salinity of salt water quickly and accurately, ideal for agriculture, industry and research application, such as Mariculture, Fish Culture, Aquarium, Marine Survey, Water Quality Monitoring, Salt Production, Manufacture of Normal Saline, Salinity Measurement in Food Processing etc. It can also be used for medical institutions and university research.
  • DUAL SCALES: The Refractometer is a equipment to measure the liquid concentration(the concentration of salt) by using the light, working basis on that the liquid with different concentrations have different light refractive index. The Measures on 2 scales: Specific Gravity (0.001, Range: 1.000 - 1.070, D 20/20,) and Parts Per Thousand (1‰, Range: 0-100‰).
  • ATC FUNCTION: Automatic Temperature Compensation during 10-30℃, eliminating data errors caused by temperature changes and guaranteeing a consistent accurate result.
  • WITH DURABLE STORAGE CASING: With a sturdy and light weighted case, it is very convenient to storage and carry. The body is made of stainless steel and is very durable, the eyepiece is in high quality for better viewing, adopting optical glass lens rather than plastic lens for accurate measurement.
  • PACKAGING: 1 x Salinity Refractometer, 1 Pipette, 1 x Instruction manual, 1 x Mini screwdriver, with a durable storage case.
  • 1 x Salinity Refractometer
  • 1 x Pipette
  • 1 x Instruction Manual
  • Manufacture: Eyourlife
  • Product Dimensions: 7.91 x 2.99 x 2.2 inches; 5.6 Ounces
  • Editor's Impressions Of The Eyourlife
  • Accuracy [star rating='3.9']
  • Quality [star rating='3.4']
  • Value For Money [star rating='4.9']
  • Affordability [star rating='5']

Eyourlife Final Thoughts

"And accurate."

I've checked about 5 times with the hydrometer and each time has been near perfect. Great tool if you have a salt-water fish tank or a decorative pond. But there are some ways to keep on getting accurate readings. Pretty darn accurate for the price. So worth it considering its great quality and great price. Does just as good of a job of any meter you would buy at the store! It is a little cheaper made but it works great for the cost!

Overall Score
4.4

[star rating="4.4"]
(18 Points)

3. Aquarium Refractometer, Seawater Salinity Meter Aquarium Optics Refractometer Temperature ATC Digita...

Hongzer First Impressions

"Easy to use."

Functions just as it is supposed to. It is essential to get some specialized aquarium calibration fluid for 1. It is easy to read and perform the procedure in seconds. It did not need adjusting to calibrate, though I tried to just to see how it worked. Once I figured that out, it works great. Be sure to buy the calibration solution and test this before use! So once your instant ocean shows a measurement.

  • Aquarium Refractometer, Seawater Salinity Meter Aquarium Optics Refractometer Temperature ATC Digital 0-10%
  • 0 to 10% salinity, 0.01% scale.
  • Durable aluminum body, durable and can use for a long time.
  • Adjust the focus by twisting the handle.
  • Compact design with rubber handle.
  • Soft and flexible eyepiece for added comfort. Instant and reliable aqueous solution measurement.
  • Manufacture: Hongzer
  • Item Weight: 8.4 ounces
  • Product Dimensions: 6.69 x 1.57 x 1.57 inches
  • Editor's Impressions Of The Hongzer
  • Accuracy [star rating='5']
  • Quality [star rating='5']
  • Value For Money [star rating='5']
  • Affordability [star rating='5']

Hongzer Final Thoughts

"So far so good."

It is a little cheaper made but it works great for the cost! Pretty darn accurate for the price. Ambient room light at night is not enough and makes what you're viewing dark. Normally that gives the more accurate reading. Now its easy to make sure I have the correct amount of salt in my aquariums. I was surprise that the product was really cheap compare to the other ones. This refractor should last a good number of years.

Overall Score
5.0

[star rating="5"]
(2 Points)

4. Digital Salinity Meter, SA287 Portable Digital Salinity Meter High Precision Salinity Temperature Pe...

Jadpes First Impressions

"Works great for reefing!"

At first, I was getting bubbles sticking to the rotating arrow. Perfrct for someone learning or anyone for that matter. Works great,& comes in a storage box. Then I made a mark on it to set the salinity of my fish tank. Bubbles can greatly affect the reading. I tried it over and over and no bubbles! I think those reviews just didn't know how to use it properly.

  • Digital Salinity Meter, SA287 Portable Digital Salinity Meter High Precision Salinity Temperature Pen Type Tester for Saltwater, Swimming Pool, Aquaculture, Aquarium
  • WATERPROOF SALINITY METER:It displays the salinity value precisely, compact size and light weight, easy and portable to carry, convenient to use.This instrument can not only detect the salt content of edible salt, salt water pool and koi fish pond, but also the salinity of seawater, marine, salt water fish tank salt level testing.
  • SALINITY TESTER:Digital Salinity Tester for Salt Water.The pen type salinity meter is a precision instrument for testing the salinity value of a solution.Quick and reliable manner for most regular water solutions' testing.
  • WIDE APPLICATIONS:Suitable for saltwater, swimming pool, aquaculture, aquarium (seawater) and pond, food processing and health care products industry. Saltwater Tester for Seawater, Aquariums, Marine Monitoring.
  • BACKLIT DESIGN:It adopts large screen LCD, PPT standard unit display, power display, power data protection function, automatic temperature compensation, dustproof and waterproof functions.
  • APPLICATION:Its full-featured performance, easy operation and replaceable electrodes make it the best choice for rapid, accurate salinity testing in laboratories, sites and schools.
  • Manufacture: Jadpes
  • Product Dimensions: 0.39 x 0.39 x 0.39 inches; 5.29 Ounces
  • Editor's Impressions Of The Jadpes
  • Accuracy [star rating='3.3']
  • Quality [star rating='2.9']
  • Value For Money [star rating='3']
  • Affordability [star rating='2.7']

Jadpes Final Thoughts

"Couldn't do without it."

YOU WILL NOT get an accurate reading if there are bubbles on the needle. It did not need adjusting to calibrate, though I tried to just to see how it worked. This is perfect to keep a check on the salt level in your tank. Make sure to knock out the bubbles on the white dial by hitting it with your knuckle. My only criticism would be that it's a little too dark. It is essential to get some specialized aquarium calibration fluid for 1. I have purchased before will buy again!

Overall Score
3.0

[star rating="3"]
(1 Points)

Honorable Mentions - More Top Selling Digital Aquarium Hydrometers

5. Digital Salinity Tester for Salt Water - Aquarium Salinity Meter with ATC, IP67 Waterproof, 0-200 PP...

CIZTADA First Impressions

"Works great for reefing!"

Functions just as it is supposed to. Looks to provide very accurate readings. Waterproof if you accidentally drop it in the pool. Does just as good of a job of any meter you would buy at the store! I have a 2000+ gallon pond and I just put salt in it last month. Comes with a nice carrying case for easy and secure transportation. Good quality and simple to use refractometer.

  • Digital Salinity Tester for Salt Water - Aquarium Salinity Meter with ATC, IP67 Waterproof, 0-200 PPT Large Range Multi-Parameter Tester for Seawater, Fish Tank, Hydroponics
  • [Large Salinity Range] Ciztada salinity tester has 2 measurement modes, scale range: 0~9999 ppm/10.0~200 ppt and 0.00-25.00%, which is 2 times than the salinity refractometer
  • [Automatic Temperature Compensation] Ciztada salinity tester is equipped with ATC part inside, during normal temperature, once calibrated, the temperature change would never affect the accurate of your measuring result. This makes it more convenient to use in different temperature
  • [Easy Reading with LCD Backlight] There is no need to worry about seeing the displayed value if the light is insufficient. Ciztada salinity meter features a green backlit LCD to help you see the measurement results clearly in any situation
  • [Multifunctional Salinity tester]: The Ciztada multi-parameter Tester can test Salinity, TDS, EC and Temperature in an accurate, quick and reliable manner for most regular water solutions' testing. Support One-tap switch from salinity to TDS/EC
  • [Wide Applications]: Measures saltwater or salinity of water, ideal for aquarium, marine monitoring, salty pools & spas, koi fish pond, hydroponics and etc
  • Manufacture: CIZTADA
  • Batteries: 3 LR44 batteries required. (included)
  • Editor's Impressions Of The CIZTADA
  • Accuracy [star rating='5']
  • Quality [star rating='4.6']
  • Value For Money [star rating='4.6']
  • Affordability [star rating='5']

CIZTADA Final Thoughts

"Accurate so far!"

Too that makes it appear too cheap. It says in the instructions to use distilled water. This is perfect to keep a check on the salt level in your tank. Normally that gives the more accurate reading. Once I adjusted the refractometer, my aquarium salinity read 1. Bought this one to check my old one, this one checked right on the dot at 1. Bought this one to check my old one, this one checked right on the dot at 1.

Overall Score
5.0

[star rating="5"]
(1 Points)

6. Bubble Magus Digital Color Screen Salinity Meter

Bubble Magus First Impressions

"Good value."

YOU WILL NOT get an accurate reading if there are bubbles on the needle. Every time I leave to do something I come back and it's at the bottom of my tank. On the shaft of the refractometer, there's a little, rubber-covered nub. However, the numbers are soooo small it is sometimes hard to read. Just rinse with warm water afterwards. I use this for my 10g brackish and it works ok. Bought this as a back up refractometer.

  • Bubble Magus Digital Color Screen Salinity Meter
  • Manufacture: Bubble Magus
  • Editor's Impressions Of The Bubble Magus
  • Accuracy [star rating='4.8']
  • Quality [star rating='5']
  • Value For Money [star rating='4.1']
  • Affordability [star rating='4.7']

Bubble Magus Final Thoughts

"Easy to use."

Functions just as it is supposed to. Be sure to buy the calibration solution and test this before use! Ambient room light at night is not enough and makes what you're viewing dark. It is a little cheaper made but it works great for the cost! I decided to upgrade and it was easy to calibrate. I would recommend this product to anyone that has a marine aquarium. So worth it considering its great quality and great price.

Overall Score
5.0

[star rating="5"]
(1 Points)

7. Automatic Temperature Compensation Sea Water Salt Salinity Refractometer for Aquarium, 0% - 10% & 1....

User Ratings: 50 10

Ade Advanced Optics Salinity10 First Impressions

"No assembly required."

I use this for my 10g brackish and it works ok. Like that it comes with everything needed. It is essential to get some specialized aquarium calibration fluid for 1. Looks to provide very accurate readings. I was surprise that the product was really cheap compare to the other ones. It is essential to get some specialized aquarium calibration fluid for 1. Hate the batteries, but once loaded, it seems to work fine.

  • Automatic Temperature Compensation Sea Water Salt Salinity Refractometer for Aquarium, 0% - 10% & 1.0 to 1.070 S.g. Dual Scale Hydrometer By Adeadvancedoptics
  • Manufacture: Ade Advanced Optics®
  • Product Dimensions: 8.7 x 2.8 x 1.42 inches; 6.4 Ounces
  • Editor's Impressions Of The Ade Advanced Optics Salinity10
  • Accuracy [star rating='4']
  • Quality [star rating='4.9']
  • Value For Money [star rating='3.3']
  • Affordability [star rating='3.2']

Ade Advanced Optics Salinity10 Final Thoughts

"Easy to use."

Small problem with bubbles on the needle but other than that no issues. This one read perfect, and the others were completely inaccurate. Then I made a mark on it to set the salinity of my fish tank. Great product I used for beer making and my saltwater aquarium. Now that it's calibrated I love it! It's fast, it's tidy, and it's accurate. 026 and the tank isn't, new animals will go into shock.

Overall Score
3.9

[star rating="3.9"]
(145 Points)

8. Clinical Refractometer with ATC, Tri-Scale Serum Plasma Protein Test 2-14g/dl Urine Specific Gravity...

Gain Express REC-300ATC First Impressions

"Matches my hydrometer."

YOU WILL NOT get an accurate reading if there are bubbles on the needle. If you let it sit in the tank overnight, it definitely gives an accurate reading. Even the smallest bubble will throw the measurements way, way off. It is easy to read and perform the procedure in seconds. Pretty darn accurate for the price. Easy to use, easy to clean, easy to read. Definitely a lot cheaper than a refractometer.

  • Clinical Refractometer with ATC, Tri-Scale Serum Plasma Protein Test 2-14g/dl Urine Specific Gravity 1.000-1.060SG, for Veterinary Vet Cat Dog Pets
  • Animal clinical refractometer Tri Scale for Dog Cat Test of Serum protein and Urine specific gravity
  • TRIPLE SCALE: Dog Scale Urine Specific Gravity is for Large Animal, Cat Scale Urine Specific Gravity is for Small Animal and Serum or Plasma Protein Scale for all animals
  • MEASURING RANGE: Dog and Cat Urine specific gravity: 1.000 - 1.060SG ; Serum Protein: 2-14g/dl
  • Cushioned w/ soft and comfortable non-slip rubberized grip, insulate test solution from body heat
  • Auto Temperature Compensation (ATC), rest easy that your measurements are always accurate regardless of temperature variation
  • Manufacture: Gain Express Holdings Ltd
  • Part Number: REC-300ATC
  • Item Weight: 9.2 ounces
  • Color: Urine Sg / Serum Protein
  • Batteries Included?: No
  • Batteries Required?: No
  • Editor's Impressions Of The Gain Express REC-300ATC
  • Accuracy [star rating='4.2']
  • Quality [star rating='5']
  • Value For Money [star rating='5']
  • Affordability [star rating='4.2']

Gain Express REC-300ATC Final Thoughts

"These seem spot on."

Great tool if you have a salt-water fish tank or a decorative pond. My only criticism would be that it's a little too dark. I decided to upgrade and it was easy to calibrate. Definitely a lot cheaper than a refractometer. Even the smallest bubble will throw the measurements way, way off. Excellent piece of equipment for the price. Small problem with bubbles on the needle but other than that no issues.

Overall Score
5.0

[star rating="5"]
(7 Points)

9. Rhinoco Salinity Refractometer, Saltwater Aquarium Refractometer, Dual Scales Specific Gravity Salin...

User Ratings: 75

Rhinoco RINTL277US First Impressions

"Great product!"

I bought this salinity meter for my aquarium. I will get one later but for now this will do, since im just starting. Get precise salinity readings in moments. Great, I be had this b4 ez to test salt level. Even the smallest bubble will throw the measurements way, way off. However, the numbers are soooo small it is sometimes hard to read. I compared the readings using this hygrometer and the calibrated refractometer.

  • Rhinoco Salinity Refractometer, Saltwater Aquarium Refractometer, Dual Scales Specific Gravity Salinity Meter with 0-100 PPT and 1.000-1.070 for Seawater, Pool, Tank, Testing, Marine Fishkeeping
  • 【Salinity Refractometer】Measure Salt Water or Salinity of Water, ideal for Aquariums, Marine Monitoring, Agricultural, Gardening & Educational Purposes.
  • 【Automatic Temperature Compensation】Salinity Tester Built-in ATC, which Accounts for Changes in Ambient Temperature and Automatically Compensates Accordingly to Guarantee Consistently Accurate Readings.
  • 【Dual Salinity Scale】Salinity Mester with Dual Scale 0-100 ppt(0 - 10 %) of Salinity and 1.000 to 1.070 Specific Gravity (0-10%).
  • 【Full Copper Chrome Plated Design】Sturdy & Compact, the Eyepiece is in High Quality for Better Viewing, Adopting Optical Glass Lens Rather than Plastic Lens for Accurate Measurement.
  • 【Accessories & Warranty】1 x Salinity Refractometer, 1 x Plastic Pipette, 1 x Mini Screw Driver, 1 x Cleaning Cloth and User Manual, Comes with 18-Month Warranty!
  • Manufacture: Rhinoco
  • Editor's Impressions Of The Rhinoco RINTL277US
  • Accuracy [star rating='3.8']
  • Quality [star rating='5']
  • Value For Money [star rating='3.9']
  • Affordability [star rating='4.5']

Rhinoco RINTL277US Final Thoughts

"So far so good."

It is a little cheaper made but it works great for the cost! Simple to use, but if there are any air bubbles the results will be way off. But with alittle persistance I am able to read it. I would suggest purchasing the salt calibration solution. I got this to have a more accurate read than the hydrometer. And it is much more accurate than my old salinity meter. Waterproof if you accidentally drop it in the pool.

Overall Score
4.8

[star rating="4.8"]
(10 Points)

10. Seawater Salinity Refractometer,V-Resourcing Automatic Temperature Compensation Sea Water Salinity M...

User Ratings: 64 8

V·RESOURCING COMINHKPR127692 First Impressions

"Good product."

I have tried others before but this has given me accurate and stable results. All very easy and I feel as though I am getting an accurate salinity reading. I did NOT calibrate, but am getting accurate readings. YOU WILL NOT get an accurate reading if there are bubbles on the needle. I run brackish tanks and it works perfectly. 027, I'm so glad I bought this one and it came spot on. Definitely a lot cheaper than a refractometer.

  • Seawater Salinity Refractometer,V-Resourcing Automatic Temperature Compensation Sea Water Salinity Measurer for Aquarium, Hydrometer, 0-100ppt & 1.000-1.070 Salinity Specific Gravity
  • Automatic Temperature Compensation: 10℃~30℃
  • Measuring range: salinity: 0-100 ‰, Specific Gravity : 1.000 to 1.070
  • Minimum scale: salinity: 1 ‰, Specific Gravity : 0.001
  • Resolution: salinity: ±1‰, Specific Gravity : 0.001 mm
  • Perfect for salty water tank and aquarium, seafood water tank, salty pools & spas and etc
  • 1*Salinity Refractometer
  • 1*Mini-screwdriver
  • 1*Pipette
  • Manufacture: V-Resourcing
  • Product Dimensions: 8 x 3 x 2 inches; 8 Ounces
  • Editor's Impressions Of The V·RESOURCING COMINHKPR127692
  • Accuracy [star rating='4.1']
  • Quality [star rating='3.3']
  • Value For Money [star rating='5']
  • Affordability [star rating='5']

V·RESOURCING COMINHKPR127692 Final Thoughts

"0, it reads 1."

However, the numbers are soooo small it is sometimes hard to read. I have to recalibrate it ever use though which worries me sometimes. When I saw the price offered on this one, I decided to buy and I love it. Not sure how accurate it is, but it's a good reference point. I would recommend this product to anyone that has a marine aquarium. Easy to use, easy to clean, easy to read. A hydrometer for making sure you have the right saltwater mix.

Overall Score
4.3

[star rating="4.3"]
(31 Points)

Copyright © 2024 Rob Aquatics — Primer Child WordPress theme by GoDaddy