Editor's Choice - Our Favorite Instant Aquarium Hydrometers

1. Instant Ocean SeaTest Hydrometer

User Ratings: 59 6

Instant Ocean TK-504 First Impressions

"Calibrate it, use it."

Make your own by simply boiling some water and collecting the condensate. This one here was much cheaper,& exactly the same as they sold in the store. My only criticism would be that it's a little too dark. Normally that gives the more accurate reading. Used distilled water to calibrate, the screw is located under the rubber cap. Once I adjusted the refractometer, my aquarium salinity read 1. Hate the batteries, but once loaded, it seems to work fine.

  • Instant Ocean SeaTest Hydrometer
  • Marine hydrometer: Tests salinity and specific gravity in marine aquariums to help maintain a healthy tank
  • Accurate: Precise, full-range readings - accurate to +/- 0
  • Ready to use: Simply dunk in aquarium to fill with water, then set on level surface to read
  • Easy to read: Clearly marked to show results
  • Extra-wide stabilizer base: Two-color scale with a safe zone for simple results
  • Manufacture: Instant Ocean
  • Item Weight: 0.8 ounces
  • Product Dimensions: 6.3 x 4.2 x 1.3 inches
  • Editor's Impressions Of The Instant Ocean TK-504
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Instant Ocean TK-504 Final Thoughts

"Good price."

Simple to use, but if there are any air bubbles the results will be way off. The instant ocean hydrometer will always be right. 026 with the new Aquatic Experts fluid. Now its easy to make sure I have the correct amount of salt in my aquariums. Looks to provide very accurate readings. Easy to use, easy to clean, easy to read. My only criticism would be that it's a little too dark.

Overall Score
4.2


(426 Points)

Peoples Choice - Other Highly Rated Instant Aquarium Hydrometers

2. KKmoon Salinity Refractometer, Handheld Seawater Hydrometers, Optical Salinity Tester, Portable ATC ...

User Ratings: 70 8

KKmoon First Impressions

"Decent case."

Hate the batteries, but once loaded, it seems to work fine. Get precise salinity readings in moments. I have a 2000+ gallon pond and I just put salt in it last month. The hydrometer is good, but I ordered two Shrimp CRS Miniature glass figurine, Clear. So once your instant ocean shows a measurement. All very easy and I feel as though I am getting an accurate salinity reading. The reading is big enough for you to read and it comes with the batteries.

  • KKmoon Salinity Refractometer, Handheld Seawater Hydrometers, Optical Salinity Tester, Portable ATC Refractometer, Dual Scale Saltwater Tester for Aquarium, Seawater, Pool, Fish Tank
  • Measure salt water or salinity of water, ideal for aquariums and marine monitoring.
  • With measurement level for direct reading. Adjustable manual focus, easy to focus and calibrate.
  • Handheld design and non-slip rubber handle for easy operation.
  • Instant Reading Result: Just need 2-3 drops of solution and a few seconds, you can get accurate readings.
  • Built-in automatic temperature compensation(ATC) to get faster results.
  • Manufacture: KKmoon
  • Item Weight: 8.9 ounces
  • Editor's Impressions Of The KKmoon
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

KKmoon Final Thoughts

"This tool is AMAZING!"

The refractor was off out off the box. I have a 2000+ gallon pond and I just put salt in it last month. Clear readout with the ability to calibrate and focus. I've tried several different refractometers now and they are mostly the same. He is too cute not to want to take care of properly. When I saw the price offered on this one, I decided to buy and I love it. Very easy, turn screw very slowly to calibrate.

Overall Score
4.2


(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
  • Quality
  • Value For Money
  • Affordability

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


(2 Points)

4. ZRM&E Seawater Hydrometer for Aquarium Aquaculture Seawater Densimeter Ocean Hydrometer Salinity Met...

User Ratings: 70 30

ZRM&E First Impressions

"Gave me confidence."

YOU WILL NOT get an accurate reading if there are bubbles on the needle. I have purchased before will buy again! I felt it wasn't accurate which was verified by my LFS. Very quick to calibrate and to use. It says in the instructions to use distilled water. I bought this refractometer as a more accurate option for salinity than a hydrometer. Don't spend your money on calibration solution.

  • ZRM&E Seawater Hydrometer for Aquarium Aquaculture Seawater Densimeter Ocean Hydrometer Salinity Meter for Fish Tank Salinity Specific Gravity Test
  • Made of high quality plastic, aquarium transparent, automatic accurate reading brine hydrometer
  • Accurate, durable and easy to read salt and specific gravity of your marine aquarium, small and waterproof. If the specific gravity is between 1.000-1.019, it indicates that the specific gravity is low; if the specific gravity is between 1.020-1.023, it indicates that the specific gravity is normal; if the specific gravity is between 1.024-1.030, it indicates that the specific gravity is high
  • The external range of the scale indicates salinity (PPT), and the internal range of the scale indicates gravity. And clearly mark the safe area. Application range: 0-40 degrees (1.000-1.030). If the salinity PPT is between 32-40, it indicates that the salinity is high; if the salinity PPT is between 27-31, it indicates that the salinity is normal; if the salinity PPT is between 0-26, it indicates that the salinity hydrometer is low
  • Wide range of applications: Suitable for salt water and sea water fish tanks. Perfect for testing salinity and specific gravity of saltwater and seawater tanks, including solubility and specific gravity scales. Suitable for fresh water and sea water
  • Easy to read swing arm pointer and ultra wide stable base can provide accurate test results
  • Manufacture: DGHP
  • Editor's Impressions Of The ZRM&E
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

ZRM&E Final Thoughts

"Great Product, Thanks!"

YOU WILL NOT get an accurate reading if there are bubbles on the needle. Get precise salinity readings in moments. If you let it sit in the tank overnight, it definitely gives an accurate reading. Compare it with the refractometer and adjust the refractometer so that it matches. Don't care much for having to post a review in order to activate warranty. Even the smallest bubble will throw the measurements way, way off. I would recommend this product to anyone that has a marine aquarium.

Overall Score
3.8


(4 Points)

5. Pen Type Salinity & Temp Meter Measurement Units Checker Quality Tester ATC for Pond Pool Saltwater ...

User Ratings: 36 25

TEKCOPLUS SMTK-49_SOL First Impressions

"So here's the verdict."

Just give me one simple, accurate reading to go by, and I'm happy. This is perfect to keep a check on the salt level in your tank. He is too cute not to want to take care of properly. Bought this as a back up refractometer. Get precise salinity readings in moments. The unit is really easy to calibrate and used. My only criticism would be that it's a little too dark.

  • Pen Type Salinity & Temp Meter Measurement Units Checker Quality Tester ATC for Pond Pool Saltwater Aquarium Cooking Seawater Drinking Water (Salinity Meter 70.0ppt + Buffer Sol'n)
  • Ideal for checking salt in fish tanks and aquariums, water monitoring, seawater-prepared food solutions, holding tanks and more!
  • Measuring Range: Salinity: 0.00~10.0 ppt (NaCL) and 10.1~70.0ppt (NaCL)
  • Auto Power-Off Function with disable feature
  • °C/°F unit switchable ,Easy one-touch calibration, Waterproof Rating: IP65
  • Calibration set: Buffer NaCI 50ppt and calibration guideline
  • Manufacture: TekcoPlus Ltd
  • Editor's Impressions Of The TEKCOPLUS SMTK-49_SOL
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

TEKCOPLUS SMTK-49_SOL Final Thoughts

"Measurement does work."

I have to recalibrate it ever use though which worries me sometimes. Just rinse with warm water afterwards. I bought this salinity meter for my aquarium. I bought this and a hydrometer because of the reviews saying its not accurate. I have gone two years in this hobby with a hydrometer. Easy to use, easy to clean, easy to read. Compare it with the refractometer and adjust the refractometer so that it matches.

Overall Score
3.6


(5 Points)

6. capetsma Salinity Tester, Accurate Sea Hydrometer Aquarium Marine Salinity Meter for Fish Tank Pond ...

User Ratings: 56 11

capetsma First Impressions

"Great Product, Thanks!"

Be sure to adjust the focus by turning the eye focal when you first receive. There are conversion charts and tables online. I have gone two years in this hobby with a hydrometer. Get precise salinity readings in moments. It is a little cheaper made but it works great for the cost! Make your own by simply boiling some water and collecting the condensate. There are conversion charts and tables online.

  • capetsma Salinity Tester, Accurate Sea Hydrometer Aquarium Marine Salinity Meter for Fish Tank Pond Water Saltwater Freshwater Specific Gravity Test
  • 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.
  • Manufacture: Capetsma
  • Editor's Impressions Of The capetsma
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

capetsma Final Thoughts

"Easy to use."

Be sure to buy the calibration solution and test this before use! If you let it sit in the tank overnight, it definitely gives an accurate reading. Plenty of info on YouTube and the web if you don't know how. Works great,& comes in a storage box. Hate the batteries, but once loaded, it seems to work fine. Too that makes it appear too cheap. So worth it considering its great quality and great price.

Overall Score
4.0


(69 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
  • Quality
  • Value For Money
  • Affordability

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


(145 Points)

8. Sinotech Hand Held Brix Honey Refractometer Rhb-90atc withCalibration Oil

Sinotech First Impressions

"This tool does that."

When I compared it to what my local pet store was reading my water at it was dead on. I would recommend this product to anyone that has a marine aquarium. Great product I used for beer making and my saltwater aquarium. Plus it is super easy to use and clean. I don't want to deal with temperature correction or. Get precise salinity readings in moments. Does just as good of a job of any meter you would buy at the store!

  • Sinotech Hand Held Brix Honey Refractometer Rhb-90atc withCalibration Oil
  • Test Fruit Brix And Honey Water
  • Heavy-duty and lightweight With its aluminum construction
  • ATC CompensationRange: 10°C~30°C (50°F~86°F)
  • Protable Type
  • 58-90%Brix 38-43 Be° (Baume) 12-27% Water
  • Manufacture: Sinotech
  • Editor's Impressions Of The Sinotech
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Sinotech Final Thoughts

"NO BUBBLES!"

I bought this and a hydrometer because of the reviews saying its not accurate. I compared the readings using this hygrometer and the calibrated refractometer. Works great,& comes in a storage box. Used distilled water to calibrate, the screw is located under the rubber cap. So worth it considering its great quality and great price. My only criticism would be that it's a little too dark. This requires repeatedly tapping the arm with a pencil.

Overall Score
3.0


(1 Points)

9. Amzdeal Salinity Refractometer Aquarium & Seawater - Dual Scale (1.0 to 1.070 S.G.)

User Ratings: 66 12

amzdeal First Impressions

"Seems to work fine."

Hate the batteries, but once loaded, it seems to work fine. For the price you definitley cant beat this meter is great! I would recommend this product to anyone that has a marine aquarium. Make sure to knock out the bubbles on the white dial by hitting it with your knuckle. I was surprise that the product was really cheap compare to the other ones. I don't want to deal with temperature correction or. This is perfect to keep a check on the salt level in your tank.

  • Amzdeal Salinity Refractometer Aquarium & Seawater - Dual Scale (1.0 to 1.070 S.G.)
  • 【Automatic Temperature Compensation】 Hand-held ATC refractometer, can be used in the temperature 5-30 ℃ / 41-86℉
  • 【Dual Salinity Scale】Salt content 0 ~ 100 ‰ (0 ~ 10%) and Salt specific gravity 1.000 ~ 1.070sg. Minimum scale is 1 ‰ (0.1%) or 0.001sg, more precise
  • 【Easy to Use】Using distilled water to calibrate and then you can measure the saltwater and get the result
  • 【Package Content】Come with all the accessories, including Dropper, Screwdriver, Cleaning Cloth, Storage Case and User Manual
  • 【Widely Use】This refractometer can be used to measure the salt content or sugar content, good for aquariums and marine monitoring
  • Manufacture: Amzdeal
  • Editor's Impressions Of The amzdeal
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

amzdeal Final Thoughts

"Massive peace of mind."

Be sure to adjust the focus by turning the eye focal when you first receive. Even the smallest bubble will throw the measurements way, way off. YOU WILL NOT get an accurate reading if there are bubbles on the needle. I use this to check the specific gravity of my marine aquarium. When I saw the price offered on this one, I decided to buy and I love it. Excellent piece of equipment for the price. Perfrct for someone learning or anyone for that matter.

Overall Score
4.2


(56 Points)

10. HydroLogic HLTDS DM-2 Industrial Monitor

HydroLogic HLTDS First Impressions

"Case is nice as well."

Don't care much for having to post a review in order to activate warranty. YOU WILL NOT get an accurate reading if there are bubbles on the needle. The water was at what I expected it should be. However, the numbers are soooo small it is sometimes hard to read. Get precise salinity readings in moments. Was calibrated and worked perfect right out of the box. I would suggest purchasing the salt calibration solution.

  • HydroLogic HLTDS DM-2 Industrial Monitor
  • Measures The Flow Of Untreated Water Coming In Versus Purified Water Going Out
  • Comes Equipped With A 1/2" Inlet And 3/8Th Inch Outlet
  • Features An Auto-Off Function To Conserve Battery Power
  • No Assembly Required
  • Manufacture: Hydro-Logic
  • Item Weight: 2.38 pounds
  • Product Dimensions: 7.2 x 5.1 x 1.7 inches
  • Editor's Impressions Of The HydroLogic HLTDS
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

HydroLogic HLTDS Final Thoughts

"Using for my Pacman frog."

Looks to provide very accurate readings. It is a little cheaper made but it works great for the cost! I've checked about 5 times with the hydrometer and each time has been near perfect. Once I figured that out, it works great. I needed this product and it is a lot less expensive than the local aquarium store. Clear readout with the ability to calibrate and focus. Easy to use, easy to clean, easy to read.

Overall Score
5.0


(1 Points)

Copyright © 2022 Rob Aquatics — Primer Child WordPress theme by GoDaddy