Editor's Choice - Our Favorite Kocome Aquarium Hydrometers

1. Kocome Marine Hydrometer Reef Fish Tank Aquarium Water Salinity Specific Gravity Tester

User Ratings: 71

Kocome First Impressions

"Great kit."

I use this for my 10g brackish and it works ok. Plus it is super easy to use and clean. I did NOT calibrate, but am getting accurate readings. I needed this product and it is a lot less expensive than the local aquarium store. It's fast, it's tidy, and it's accurate. But with alittle persistance I am able to read it. Don't care much for having to post a review in order to activate warranty.

  • Kocome Marine Hydrometer Reef Fish Tank Aquarium Water Salinity Specific Gravity Tester
  • Accurate and easy to read.
  • Size: 3.54×4.72×0.59in (Approx.).
  • Readings are temperature-corrected & accurate to +/- 0. 002 specific gravity units which range from 1. 000 - 1. 030 specific gravity.
  • It is optimum to be put into below 6" deep water, so it can avoid the error from the oil slick.
  • Perfect for testing both salinity and specific gravity of your brackish and marine tank.
  • Manufacture: KOCOME
  • Editor's Impressions Of The Kocome
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Kocome Final Thoughts

"026 as expected."

I would recommend you to purchase this and skip the other ones. I have tried others before but this has given me accurate and stable results. On the shaft of the refractometer, there's a little, rubber-covered nub. I couldn't decide between this and one of the float arm meters or both. Very easy, turn screw very slowly to calibrate. Looks to provide very accurate readings. The instant ocean hydrometer will always be right.

Overall Score
4.6


(9 Points)

2. AUTOUTLET Refractometer Saltwater Aquarium for Seawater,Pool,Tank,Testing,Marine Fishkeeping, 0-100P...

User Ratings: 83 2

AUTOUTLET 8541957195 First Impressions

"These seem spot on."

Not sure how accurate it is, but it's a good reference point. Ambient room light at night is not enough and makes what you're viewing dark. If you read the directions in the box for the refractometer it's for freshwater. And it is much more accurate than my old salinity meter. Waterproof if you accidentally drop it in the pool. My corals will be much happier now. It is a little cheaper made but it works great for the cost!

  • AUTOUTLET Refractometer Saltwater Aquarium for Seawater,Pool,Tank,Testing,Marine Fishkeeping, 0-100PPT & 1.000-1.070 Salinity Tester with ATC Function Hydrometer Specific Gravity Salinity Meter Kit
  • 【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.
  • Due to the difference of human focal lengths,when during adjusting, you may just need to rotate in reverse or re-adjust the distance between your eye and the eyepiece.
  • It's necessary to keep the surrounding environment with sufficient brightness and suitable temperature during use. Generally,there is no error in the temperature between 10℃-30℃.(50℉-86℉)
  • Specific Gravity (D 20/20) and parts per thousand and replaces your poor quality and difficult to read hydrometer.
  • Manufacture: AUTOUTLET
  • Product Dimensions: 7.87 x 3.54 x 2.36 inches; 8.48 Ounces
  • Editor's Impressions Of The AUTOUTLET 8541957195
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

AUTOUTLET 8541957195 Final Thoughts

"2 failed, 3 did not."

Just rinse with warm water afterwards. I bought this and a hydrometer because of the reviews saying its not accurate. Now that it's calibrated I love it! I HIGHLY recommend this to Aquarists! I have purchased before will buy again! I got this to have a more accurate read than the hydrometer. Too that makes it appear too cheap.

Overall Score
4.7


(757 Points)

3. Coralife Energy Savers ACLAF877 Deep Six Hydrometer

User Ratings: 67 7

Coralife 100108103 First Impressions

"024 and my refracto read."

I found mine was calibrated out of the box. At first, I was getting bubbles sticking to the rotating arrow. Wipe down glass surface to dry it and put it back on the shelf til next time. So once your instant ocean shows a measurement. Does just as good of a job of any meter you would buy at the store! I tried it over and over and no bubbles! Simple to use, but if there are any air bubbles the results will be way off.

  • Coralife Energy Savers ACLAF877 Deep Six Hydrometer
  • 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
  • Specific Gravity and Salinity PPT Scales
  • Optimal Specific Gravity / Salinity range indicator on scale
  • Manufacture: Central Garden & Pet
  • Product Dimensions: 6.69 x 0.79 x 4.72 inches; 3.2 Ounces
  • Editor's Impressions Of The Coralife 100108103
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Coralife 100108103 Final Thoughts

"Easy instructions."

I couldn't decide between this and one of the float arm meters or both. Once I figured that out, it works great. Now its easy to make sure I have the correct amount of salt in my aquariums. I use this for my 10g brackish and it works ok. My only criticism would be that it's a little too dark. I will update later to see if the refractor will keep its calibration. The instant ocean hydrometer will always be right.

Overall Score
4.3


(543 Points)

4. Dual Scale Salinity Refractometer ATC 0-100ppt (0-10%) & 1.000-1.070 Specific Gravity, Portable Mete...

User Ratings: 76 4

Gain Express RES-10ATC First Impressions

"Documentation is limited."

So once your instant ocean shows a measurement. And always make sure there is no bubbles on the measuring unit. Make sure to knock out the bubbles on the white dial by hitting it with your knuckle. But with alittle persistance I am able to read it. Make your own by simply boiling some water and collecting the condensate. Works great,& comes in a storage box. Trying to turn it by hand won't work.

  • Dual Scale Salinity Refractometer ATC 0-100ppt (0-10%) & 1.000-1.070 Specific Gravity, Portable Meter Tester for Seawater Salt Sea Water Aquarium Brackish Reef Tank Marine
  • Range: 0-100ppt (0-10% Salinity) and Density/ Specific Gravity 1.000-1.070 1ppt Salinity and 0.001 g/cm3 Density Resolutions
  • Water or a salt (brine) refractometer preferred by aquarist, it checks saltwater & brine or salinity of water, best for aquariums and marine monitoring
  • True seawater or a salt (brine) refractometer preferred by aquarist
  • Calibrate simply by distilled water, comes with free screwdriver for calibration
  • Has automatic temperature compensation (ATC) and has built with the highest and finest quality of aluminum & rubbe
  • Manufacture: Gain Express Holdings Ltd
  • Part Number: REB-32ATC
  • Material: ABS Material for Handle
  • Item Weight: 9.9 ounces
  • Color: 0-10% Salinity
  • Batteries Included?: No
  • Batteries Required?: No
  • Editor's Impressions Of The Gain Express RES-10ATC
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Gain Express RES-10ATC Final Thoughts

"Good product."

For the price you definitley cant beat this meter is great! Now its easy to make sure I have the correct amount of salt in my aquariums. Comes with a nice carrying case for easy and secure transportation. Get precise salinity readings in moments. I have tried others before but this has given me accurate and stable results. Im using it for trying to create water conditions for amano zoes. I couldn't decide between this and one of the float arm meters or both.

Overall Score
4.6


(49 Points)

5. AUTOUTLET Salinity Refractometer for Aquarium Salinity Tester with ATC and Dual Scale 0-100‰ & 1.0...

User Ratings: 89

AUTOUTLET First Impressions

"Better than nothing."

027, I'm so glad I bought this one and it came spot on. Then I made a mark on it to set the salinity of my fish tank. Once I adjusted the refractometer, my aquarium salinity read 1. If you let it sit in the tank overnight, it definitely gives an accurate reading. It's a basic but reliable refractomer I use it for my aquariums. I think those reviews just didn't know how to use it properly. Used distilled water to calibrate, the screw is located under the rubber cap.

  • AUTOUTLET Salinity Refractometer for Aquarium Salinity Tester with ATC and Dual Scale 0-100‰ & 1.000-1.070 Specific Gravity Saltwater Tester for Seawater Pool Fish Tank
  • Dual scale display provides readings of one-thousandth (0-100PPT) and specific gravity (1.000 to 1.070 SG), and replace the hydrometer for easier and more accurate measurement.
  • Automatic temperature compensation. With the help of the ATC function, the salt water tester can automatically compensate for changes in the ambient temperature, which can obtain accurate readings faster and more easily.
  • Durable and portable, the salt water tester is made of non-staining, non-corrosive and non-reactive aluminum material, with superb technology, strong and durable, light weight and easy to carry.
  • Widely used, can be used for aquarium, marine monitoring, agriculture, horticulture and educational purposes (biological projects).
  • Easy to use, salinity refractometer is easy to operate, only 2 drops of sample after calibration can get accurate reading through eyepiece.
  • Due to the difference of human focal lengths,when during adjusting, you may just need to rotate in reverse or re-adjust the distance between your eye and the eyepiece.
  • It's necessary to keep the surrounding environment with sufficient brightness and suitable temperature during use. Generally,there is no error in the temperature between 10℃-30℃.(50℉-86℉)
  • Specific Gravity (D 20/20) and parts per thousand and replaces your poor quality and difficult to read hydrometer.
  • Manufacture: AUTOUTLET
  • Editor's Impressions Of The AUTOUTLET
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

AUTOUTLET Final Thoughts

"Arrived quickly."

It works, we'll i assume it does as i have nothing to compare it to. For the price you definitley cant beat this meter is great! If you read the directions in the box for the refractometer it's for freshwater. Im using it for trying to create water conditions for amano zoes. 027, I'm so glad I bought this one and it came spot on. 027, I'm so glad I bought this one and it came spot on. Even the smallest bubble will throw the measurements way, way off.

Overall Score
4.9


(14 Points)

6. Pet Dog Cat Refractometer Pet Urine Specific Gravity Refractometer Serum Plasma Protein: 2~14g/dl, C...

User Ratings: 66 16

RZ First Impressions

"Clear directions."

Trying to turn it by hand won't work. The water was at what I expected it should be. I would recommend this product to anyone that has a marine aquarium. The instant ocean hydrometer will always be right. And it is much more accurate than my old salinity meter. This requires repeatedly tapping the arm with a pencil. Bubbles can greatly affect the reading.

  • Pet Dog Cat Refractometer Pet Urine Specific Gravity Refractometer Serum Plasma Protein: 2~14g/dl, Clinical Animal Refractometer Hydrometers Urine Tester 1.000-1.060SG for Veterinary Cat Dog Pets
  • TRIPLE SCALES REFRACTOMETER: Left scale for testing urine specific gravity of large animals such as dog, the middle scale can measure cats urine specific gravity or other small animals, the right scale tests serum or plasma protein level for all animals.
  • QUICK & EASY OPERATION: few sample than other lab hydrometers, just 2 or 3 drops of solution and wait for a few seconds, accurate data automatic shows, automatic temperature compensation 0°C-30°C/50°F to 86°F
  • MEASURING RANGE: Serum or plasma protein: 2-14g/dl, large animal like dog and small animals like cats’ urine specific gravity 1.000~1.060 SG, resolution: 0.001SG. Ideal for your home pets, clinical veterinary and pet owners.
  • DURABLE REFRACOMTER: comfortable holding and non-slip ABS rubberized grip, anti-rust aluminum body for long term using. Strictly quality and safety standards approved.
  • COMPACT SIZE: Lightweight and pocket size lab refractometer, comes with sturdy plastic box, mini screwdriver, pipette and wiping cloth and manual packed together, easy to carry and storage.
  • Manufacture: RZ
  • Editor's Impressions Of The RZ
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

RZ Final Thoughts

"These seem spot on."

I have tried others before but this has given me accurate and stable results. Now that it's calibrated I love it! I use this to check the specific gravity of my marine aquarium. Looks to provide very accurate readings. Get precise salinity readings in moments. Make your own by simply boiling some water and collecting the condensate. I use this for my 10g brackish and it works ok.

Overall Score
4.0


(8 Points)

7. TOPINCN Square Saltwater Hydrometer Salt Water Salinity Meter Accurate Automatic Hydrometer Salt Wat...

TOPINCN First Impressions

"Super easy to use."

Then I made a mark on it to set the salinity of my fish tank. This device is a godsend and so much easier and cleaner to use. 027, I'm so glad I bought this one and it came spot on. I would recommend you to purchase this and skip the other ones. This refractor should last a good number of years. Find a good light source to make reading easier. Just rinse with warm water afterwards.

  • TOPINCN Square Saltwater Hydrometer Salt Water Salinity Meter Accurate Automatic Hydrometer Salt Water Salinity Meter for Fish Tank
  • Accurate, durable, and easy to read sea water hydrometer
  • This product is designed with an automatic level function, can automatically identify the level to avoid errors
  • Very accurate measurement readings, please rest assured to purchase
  • And each hydrometer has a laser engraved patent number
  • Fit for brackish and marine aquariums. Perfect for testing both salinity and specific gravity of your brackish and marine tanks.
  • Manufacture: TOPINCN
  • Product Dimensions: 5.51 x 3.54 x 0.79 inches; 3.17 Ounces
  • Editor's Impressions Of The TOPINCN
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

TOPINCN Final Thoughts

"Case is nice as well."

The refractor was off out off the box. It works OK but seems pretty flimsy and it's feel that way. I got this to have a more accurate read than the hydrometer. This device is a godsend and so much easier and cleaner to use. Bubbles can greatly affect the reading. Be sure to adjust the focus by turning the eye focal when you first receive. Ambient room light at night is not enough and makes what you're viewing dark.

Overall Score
5.0


(1 Points)

8. KOOBOOK 1 Pcs Accurate Hydrometer Salinity Meter 1.000-1.027 Salinity Range 0-36 for Aquarium Fish T...

User Ratings: 44 27

KOOBOOK First Impressions

"0, it reads 1."

Not sure how accurate it is, but it's a good reference point. I will get one later but for now this will do, since im just starting. It is heavy and easy to read in any light. Find a good light source to make reading easier. It works, we'll i assume it does as i have nothing to compare it to. If you read the directions in the box for the refractometer it's for freshwater. Good quality and simple to use refractometer.

  • KOOBOOK 1 Pcs Accurate Hydrometer Salinity Meter 1.000-1.027 Salinity Range 0-36 for Aquarium Fish Tank Marine Sea Saltwater
  • Made of high quality plastic, Withstand voltage,high transparency.
  • Special for culture of marine fish, the specific gravity and salinity of seawater are displayed once, easy to use and easy to read.
  • Keeping your hands clean,go underwater 15 cm (6 inch) depth to avoid errors caused by inhalation of oil film on the top of water.
  • When the water reaches full state (with the top of the baffle level), filed a hydrometer, this product can be hand or hang in the cylinder, automatic level function, can automatically find out the level to avoid the error.
  • Proper salinity level is one of the most important factors in the health of the fish.Readable and accuracy can up to ± 0.002 gravity unit.
  • Manufacture: KOOBOOK
  • Editor's Impressions Of The KOOBOOK
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

KOOBOOK Final Thoughts

"This tool does that."

It works, we'll i assume it does as i have nothing to compare it to. But with alittle persistance I am able to read it. I have purchased before will buy again! I have to recalibrate it ever use though which worries me sometimes. This requires repeatedly tapping the arm with a pencil. I would suggest purchasing the salt calibration solution. The reading is big enough for you to read and it comes with the batteries.

Overall Score
3.3


(11 Points)

9. Ade Advanced Optics aaosal-B Automatic Temperature Compensation Sea Water Salinity Refractometer for...

User Ratings: 26 41

Ade Advanced Optics aaosal-B First Impressions

"Be well my friend."

Comes with a nice carrying case for easy and secure transportation. I have gone two years in this hobby with a hydrometer. It says in the instructions to use distilled water. Good quality and simple to use refractometer. The refractor was off out off the box. It is heavy and easy to read in any light. I use this for my 10g brackish and it works ok.

  • Ade Advanced Optics aaosal-B Automatic Temperature Compensation Sea Water Salinity Refractometer for Aquarium, 0% - 10% and 1.0 to 1.070 S.G. Dual Scale Hydrometer, Black
  • Manufacture: Ade Advanced Optics
  • Editor's Impressions Of The Ade Advanced Optics aaosal-B
  • Accuracy
  • Quality
  • Value For Money
  • Affordability

Ade Advanced Optics aaosal-B Final Thoughts

"Couldn't be happier."

Would be nice if stem were slightly larger for easier read. Looks to provide very accurate readings. Works well on my Saltwater Aquarium. I've tried several different refractometers now and they are mostly the same. 027, I'm so glad I bought this one and it came spot on. I use this to check the specific gravity of my marine aquarium. I felt it wasn't accurate which was verified by my LFS.

Overall Score
3.0


(4 Points)

10. 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)

Copyright © 2021 Rob Aquatics — Primer Child WordPress theme by GoDaddy