Aquatic Experts Accurate refractometer calibration fluid vs. Hanna calibration fluid

[maiv_2000]

hello,

i use Aquatic Experts Accurate refractometer calibration fluid to calibrate my refractometer and Hanna instrument's calibration fluid for the Hannah salinity/temp device.

these two fluids are NOT the same. which one do i believe? the are about 4-5 ppt different.

 

[slingfox]

When I started in the hobby last year I bought a $35 refractometer from one of the big aquarium goods supplier. I subsequently got a 3 different Hanna checkers since I could not get them to match. I eventually bit the bullet and got one of the $100+ Vee Gee refractometers off Amazon and found out the $35 refractometer I had been using was completely off (giving consistently lower salinity). The Vee Gee and Hanna give very close readings when calibrated.

If you have a high quality refractometer, it should theoretically be more accurate than the Hanna. If you have one of those cheap models then you may want to upgrade.

 

[slingfox]

hello,

i use Aquatic Experts Accurate refractometer calibration fluid to calibrate my refractometer and Hanna instrument's calibration fluid for the Hannah salinity/temp device.

these two fluids are NOT the same. which one do i believe? the are about 4-5 ppt different.

Also, the objective way to test is look at the mixing instructions for your salt. Mix up a batch and see which instrument generates the closer reading. Also, I believe @Randy Holmes-Farley has instructions on this message board on how to make your own refractometer calibration solution.

 

[Koleswrath]

Also, I believe @Randy Holmes-Farley has instructions on this message board on how to make your own refractometer calibration solution.

Yes, mixing a batch of your own calibration solution each time you want to check your refractometer is my go to method. I typically do it once every few months or if I'm accidentally rough with my refractometer.
The commercially available solutions could be affected by evaporation depending on their age so I don't like to use them.

 

[slingfox]

Here is Randy's instructions on how to make calibration solution. I am switching to this method going forward. My recommendation is get a very high quality refractometer. That will save a lot of confusion and frustration (eg, I went through 3 of the Hanna checkers since I could not get any to match with the cheap refractometer thought was accurate):

http://reefkeeping.com/issues/2004-06/rhf/index.htm

 

[Randy Holmes-Farley]

hello,

i use Aquatic Experts Accurate refractometer calibration fluid to calibrate my refractometer and Hanna instrument's calibration fluid for the Hannah salinity/temp device.

these two fluids are NOT the same. which one do i believe? the are about 4-5 ppt different.

When you say they are not the same, that means what exactly?

They are intended to calibrate different types of devices, and may not work on the other type, depending on how exactly they are made.

My DIY recipes vary by device type.