Editor's Choice - Our Favorite Aquarium Equip Aquarium Hydrometers

1. Aquarium Equip UP Glass Saltwater Hydrometer - Reef Soft Coral Salinity Marine Fish Shrimp sea

User Ratings: 55 17

Aquarium Equip D667 UP??????? First Impressions

"No assembly required."

Hate the batteries, but once loaded, it seems to work fine. And it is much more accurate than my old salinity meter. Be sure to buy the calibration solution and test this before use! My only criticism would be that it's a little too dark. It is a little cheaper made but it works great for the cost! It works, we'll i assume it does as i have nothing to compare it to. I was surprise that the product was really cheap compare to the other ones.

• Aquarium Equip UP Glass Saltwater Hydrometer - Reef Soft Coral Salinity Marine Fish Shrimp sea
• 1. Easy to use 2. Green indicators are ideal range of water temperature and specific gravity for most salt water / marine aquariums 3. Hydrometer measures specific gravity 4. Need it for raising brine shrimp
• Manufacture: D667 UP玻璃海水比重計
• Product Dimensions: 0.8 x 0.8 x 6.2 inches; 0.3 Ounces

• Editor's Impressions Of The Aquarium Equip D667 UP???????
• Accuracy [star rating='3.6']
• Quality [star rating='3.6']
• Value For Money [star rating='4']
• Affordability [star rating='4.1']

Peoples Choice - Other Highly Rated Aquarium Equip Aquarium Hydrometers

2. Dr. Marine Saltwater Marine Aquarium Salinity Portable Refractometer Meter ATC 0~10% reef

Aquarium Equip D-803 UP鹽度檢測器 First Impressions

"Great Product, Thanks!"

I bought this and a hydrometer because of the reviews saying its not accurate. Great product I used for beer making and my saltwater aquarium. Bought this one to check my old one, this one checked right on the dot at 1. I needed this product and it is a lot less expensive than the local aquarium store. Simple to use, but if there are any air bubbles the results will be way off. I have purchased before will buy again! Don't spend your money on calibration solution.

• Dr. Marine Saltwater Marine Aquarium Salinity Portable Refractometer Meter ATC 0~10% reef
• This latest salinity refractometer is designed for testing the concentration of salt water and brine and used for quality control in research and clinical laboratories and marine industry. Its scale provides a direct reading of the specific gravity and concentration (Parts per Thousand) of salt in water.
• Manufacture: UP AQUA

• Editor's Impressions Of The Aquarium Equip D-803 UP鹽度檢測器
• Accuracy [star rating='4.1']
• Quality [star rating='5']
• Value For Money [star rating='5']
• Affordability [star rating='4.2']

Here Are Some Other Related Aquarium Hydrometers

3. 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']

4. 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']

5. 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 [star rating='4.4']
• Quality [star rating='4']
• Value For Money [star rating='3.8']
• Affordability [star rating='4.8']

6. Pen Type Salinity & Temperature Meter ATC NaCl Salt Water Quality Tester for Saltwater Aquarium Hydr...

User Ratings: 49 17

Gain Express 837-2 First Impressions

"Easy to calibrate."

Just rinse with warm water afterwards. I run brackish tanks and it works perfectly. Hate the batteries, but once loaded, it seems to work fine. I tried it over and over and no bubbles! Excellent piece of equipment for the price. The water was at what I expected it should be. 026 and the tank isn't, new animals will go into shock.

• Pen Type Salinity & Temperature Meter ATC NaCl Salt Water Quality Tester for Saltwater Aquarium Hydroponics Food
• MEASURING RANGE: 0~9999 ppm or 10.0ppt~100.0ppt or 0.0%~10.0% or 0.950~1.080 (S.G.) based on NaCl with ±%F.S ±1 digit / ±0.5°C Accuracy
• DISPLAY: Dual Temperature and Salinity in four measurement units (ppm, ppt, %, S.G) / 30 x 18mm LCD Size
• APPLICATION: Salinity measurement in fish pond, tank, aquariums, laboratories, food processing, hydroponics, Aquaculture, and other water monitoring facilities.
• FEATURES: Waterproof IP65 / One touch calibration / Auto power off and Non-Sleep mode disable / Multi points calibration
• POWER SUPPLY / SENSOR : 4 x LR44 button batteries
• User friendly easy to operate with One-touch calibration
• Manufacture: Gain Express Holdings Ltd
• Batteries: 4 LR44 batteries required.

• Editor's Impressions Of The Gain Express 837-2
• Accuracy [star rating='3.2']
• Quality [star rating='4.1']
• Value For Money [star rating='3.2']
• Affordability [star rating='3.8']

7. Rhino Clinical Pet (Dog & Cat) Refractometer HR305 (ATC), Urine Specific Test

RHINO TECHNOLOGY First Impressions

"Easy to use."

If you let it sit in the tank overnight, it definitely gives an accurate reading. It's perfectly accurate based on the known calibration fluid. Functions just as it is supposed to. Plenty of info on YouTube and the web if you don't know how. I don't want to deal with temperature correction or. I've tried several different refractometers now and they are mostly the same. YOU WILL NOT get an accurate reading if there are bubbles on the needle.

• Rhino Clinical Pet (Dog & Cat) Refractometer HR305 (ATC), Urine Specific Test
• The Rhino Pet refractometer HR305 can be used to read Specific Gravity of Dog Urine, Specific Gravity of Cat Urine,and Serum or Plasma Protein.
• We provide 2 years quality warranty and customize services for the Pet refractometer.
• The surface of the refractometer is sprayed with Teflon,It has the characteristics of wear resistance, corrosion resistance, anti-static and anti-adhesion.
• The Rhino Pet hand-held Refractometer come with portable holster, water bottle, calibration mini-screwdriver, english instruction manual, cleaning cloth, plastic pipette and case.
• Rhino Pet refractometer with Automatic Temperature Compensation ( 50°F~86°F / 10°C~30°C ).
• Manufacture: RHINO TECHNOLOGY

• Editor's Impressions Of The RHINO TECHNOLOGY
• Accuracy [star rating='5']
• Quality [star rating='4.4']
• Value For Money [star rating='5']
• Affordability [star rating='5']

8. 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 [star rating='5']
• Quality [star rating='4.2']
• Value For Money [star rating='4.9']
• Affordability [star rating='5']

9. 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 [star rating='4.5']
• Quality [star rating='5']
• Value For Money [star rating='4.7']
• Affordability [star rating='3.9']

10. Hikari AccuProbe Aquarium Hydrometer, Mini

User Ratings: 55 45

Hikari 96005 First Impressions

"NO BUBBLES!"

However, the numbers are soooo small it is sometimes hard to read. Make sure to knock out the bubbles on the white dial by hitting it with your knuckle. It's fast, it's tidy, and it's accurate. I did NOT calibrate, but am getting accurate readings. Definitely a lot cheaper than a refractometer. Ultimately, the measurement was exactly the same as our old tester. Calibrate with distilled water and test every so often.

• Hikari AccuProbe Aquarium Hydrometer, Mini
• Ideally suited for use in Nano tanks, smaller setups or sumps of larger systems
• Accurate to 0.001 specific gravity and salinity (PPT) measurements
• Durable construction for extended life
• Designed to give a temperature-corrected reading in warm water aquariums – 68°F to 85°F (20°C to 30°C)
• Readings can be taken by taking the meter out of the aquarium and placing on a level surface or leveling the unit in the substrate
• Manufacture: Phillips Feed & Pet Supply Natural Balance
• Product Dimensions: 5.2 x 1 x 3.5 inches; 0.8 Ounces

• Editor's Impressions Of The Hikari 96005
• Accuracy [star rating='3.9']
• Quality [star rating='3.8']
• Value For Money [star rating='2.2']
• Affordability [star rating='4']