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Full Range Hydrometer

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$16.94

$ 8 .99 $8.99

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About this item

  • No-wet-hands-design


Aquarium Systems - IO INSTANT OCEAN HYDROMETER. Instant Ocean


Andy from FL
Reviewed in the United States on March 7, 2025
Quick and easy to use but the unit I got read .001 lower than actual. I verified this with a refractometer which was calibrated with a calibration solution. Actual water was 1.026, this read 1.025. The Coral Life unit was off by .003 which I consider totally unacceptable.
Brian
Reviewed in the United States on July 14, 2022
It's cheap and it's the most accurate hydrometer I have used, other brands like coralife for instance have major quality control issues in my opinion.
Kurt
Reviewed in the United States on January 28, 2022
Gravity testers are great but to get true accuracy a hydrometer is the best way to go. With that said this will get you close enough to keep you fish alive. I wouldn’t use it for taking care of coral but just a saltwater fish tank it’s perfect
Don
Reviewed in the United States on January 14, 2021
So far every time I used it air bubbles stuck to the indicator arm, I had to find something to stick in the top to knock the bubbles off. The lettering for the salt salinity is in a different color BUT it's very hard for my 50 year old eyes to tell the difference. I paid a few extra bucks for the instant ocean hydrometer because in the picture it looks easy to read. I was wrong. If you look at the picture on Amazon they have thick red lettering for the salt salinity ranges, mine isn't like that at all. I feel I didn't really get what was advertised.
Audrey
Reviewed in the United States on April 1, 2021
Works exactly like I thought it would, had no problems with it at all. More accurate than my refractometer; easier to use at least.
Sheldon walker
Reviewed in the United States on June 5, 2020
I’m sure this isn’t normal for them to come, but mine straight out of the box doesn’t work. Every time I dip it into the water it comes with a different reading. I even tried my normal tap water and it comes up with off the charts readings. I cleaned it out and did everything I could to try and get it to work.
Joseph Cuna
Reviewed in the United States on February 24, 2020
This unit has work Flawless so far. When comparing it with my buddies more expensive tester I get the exact same reading as him. Follow the instructions and rinse it out with fresh water after each use to maintain accurate readings. The Saltwater has caused the writing or e to come off a little bit where the reading is displayed, it is not bad nor is it all coming off at once just what I would expect from using it several times in saltwater. I scratched a line where I want my salinity to be which makes it easier for the wife to read anyway.
KS in WA
Reviewed in the United States on July 28, 2019
By far the easiest way to measure salinity in water. Just fill it and let the pointer settle. Rinse it out and pack it away. Not the greatest precision, but for most purposes its more than adequate.