Refractometer V. Hydrometer!

[121a]

Ok so i always said to get one to noobs along with many many others, but i never had one

So i accidentally pressed add to cart on Premuim Aquatics website, when i was getting a pump and UV, my dad was paying for. Now he knows and doesn't really care but anyway on the main point. I know people have always said to get refractometers but i never seen any comparisons so here they are:

With the Hydrometer:

150g system: 1.022

My 27g system: 1.021-1.022

YES I DID CLEAN IT OUT VERY WELL AFTER EACH USE!

 

Now with the Refractometer:

150g System: 1.020

27g system: 1.019

I calibrated it with 53mS salinity calibration fluid for pinpoint monitors (1.026sg)

 

I feel like such a nerd, "hey guys look what i got, a REFRACTOMETER!!!"

Needless to say i trust the Refractometer way more than the hydrometer.

Anyone else gots some comparisons they care to share?

[Scott Riemer]

Ok so i always said to get one to noobs along with many many others, but i never had one

So i accidentally pressed add to cart on Premuim Aquatics website, when i was getting a pump and UV, my dad was paying for. Now he knows and doesn't really care but anyway on the main point. I know people have always said to get refractometers but i never seen any comparisons so here they are:

With the Hydrometer:

150g system: 1.022

My 27g system: 1.021-1.022

YES I DID CLEAN IT OUT VERY WELL AFTER EACH USE!

 

Now with the Refractometer:

150g System: 1.020

27g system: 1.019

I calibrated it with 53mS salinity calibration fluid for pinpoint monitors (1.026sg)

 

I feel like such a nerd, "hey guys look what i got, a REFRACTOMETER!!!"

Needless to say i trust the Refractometer way more than the hydrometer.

Anyone else gots some comparisons they care to share?

Just that when I got mine a long time ago, my Deep Six hydrometer read 1.025. When I got my refractometer, I discovered it was really 1.030.

[jm82792]

I decided to spend the money initially on a refractometer

$33 off of ebay I'm happy Atleast I will have insurance of my salinity..

[animalrie]

When I first started up my tank, I bought a hydrometer thinking about saving money. Well, after a few months, my hydrometer decided not to tell me the truth. I had no idea what my salinity was. I bought a refractometer then and have been happy since.

[Gomer]

hydrometers measurements are calibrated for an exact temperature. I think it is 80deg F. If your water isn't at this temperature, then it automatically will give a false reading.

 

Not sure on the sensitivity difference between say 80 and 77 deg. Maybe it is 1.0240 vs 1.0241 or it could be 1.024 vs 1.027. I haven't bothered to do the math

[archx]

I was having an issue where my refractometer would measure something like 1.045 while my 2 hydrometers would measure about 1.024. Turns out I was calibrating the 53.0 mS calibration fluid to 53 on the ppt scale on the refractometer . (instructions would have helped)

 

Anyway, re-calibrated the refractometer using 35 ppt and it now measures 1.025.

[Laura6686]

Just that when I got mine a long time ago, my Deep Six hydrometer read 1.025. When I got my refractometer, I discovered it was really 1.030.

 

Amazing results and great information. I have had 2 different brands of hydrometers and both give inconsistent results.

 

See that is why nano-reef is such a great resource.

[Phixion]

I have the 3 main S.G. measuring methods in my arsenal, an IO hydrometer (that I only used for a few months when I started reefing before switching up), a Premium Aquatics refractometer, and the Aqua-Mate digital salinity meter (similar to the JBJ Digi-Lab). I never compared my hydro to anything, but i DID once compare the refracto to the Aqua-Mate digital. I calibrated the refracto to 1.000 S.G. using RO/DI. I then used the 30ppt solution that comes with the Aqua-Mate, on the refracto and it measured out perfectly to 30ppt salinity. Good, that affirms that i CAN successfully calibrate using RO/DI without fear of prisim shift or so I think... I then calibrated the Aqua-Mate to 30ppt per the instructions and then tested my saltwater in my tank. Refracto read 1.025 S.G. while the Aqua-Mate read 1.023... With both perfectly calibrated I'm not sure which to trust as the digital is supposedly more accurate, but I use the digital 99.8% of the time anyways due to it's SUPER easy ease of use. I did that test months ago, I should try it again...

[d0ughb0y]

just curious, do you get a reading of 1.0 if you use tap water on the hydrometer?

I do on mine. If your hydrometer is giving a false (higher) reading, then the tap water reading should give you higher than 1.0 reading. Then you can adjust accordingly. specific gravity is on a linear scale. Unless someone can point out a scientific paper that challenges Archimedes' Principle, I think a "properly" used hydrometer will give a good reading. just my opinion.

[filefish949]

he he he I just love these threads, I like swingarm hydrometers

[Rocket]

Just did the test.

 

Refractometer: 1.025

 

Hydrometer: 1.0245

 

Sweet deal!

[d0ughb0y]

A refractometer is calibrated using a liquid with known reading before using.

If you calibrate the hydrometer using the same liquid and note the offset on the scale, then the hydrometer will give a correct reading after adding/subtracting the offset. An uncalibrated refractometer will give you a wrong reading.