Hanna and Refractometer 12ppt different

buruskeee · Oct 12, 2023

Randy Holmes-Farley said:
I may have missed it, but what refractometer are you using, and what calibration fluid?

I used an Amazon generic refractometer that has auto temp compensation. I used the Hanna salinity checker 35ppt calibration solution as I figured the salinity would work the same.

buruskeee · Oct 12, 2023

Ok, so I calibrated by using RODI water instead and calibrated to 0ppt. Still reads high but barely. It’s now reading my tank water at 36.5ppt.

Think I’m going to just take this refractometer back or try some calibration fluid from my LFS today. Still going to get my water tested by then too. At least I don’t have to worry about 120% high salinity - I think I can rule that out.

Dburr1014 · Oct 12, 2023

buruskeee said:
I’m using the digital Hanna Salinity Checker that uses conductivity.

If the fluid is 1.026, shouldn’t it read the same for the refractometer?

Nope. Refraction and conductivitiy are different. One will not read the other correctly.

Dburr1014 · Oct 12, 2023

buruskeee said:
Ok, so I calibrated by using RODI water instead and calibrated to 0ppt. Still reads high but barely. It’s now reading my tank water at 36.5ppt.

Think I’m going to just take this refractometer back or try some calibration fluid from my LFS today. Still going to get my water tested by then too. At least I don’t have to worry about 120% high salinity - I think I can rule that out.

Make a diy refractometer calibration fluid.
It is better to calibrate refractometer to fluid than rodi water regardless of the directions.

Look in here for it.

https://reefkeeping.com/issues/2004-06/rhf/index.php

Troylee · Oct 12, 2023

Get a plastic hydrometer and leave the fancy toys in the drawer.. it’s all I use and works fine! Instant ocean one from petco. Lol. It might be off a little but it’s consistently off so it works great! Haha

buruskeee · Oct 12, 2023

Dburr1014 said:
Make a diy refractometer calibration fluid.
It is better to calibrate refractometer to fluid than rodi water regardless of the directions.

Look in here for it.

https://reefkeeping.com/issues/2004-06/rhf/index.php

I’ll try this now. Thanks!

Randy Holmes-Farley · Oct 12, 2023

buruskeee said:
I used an Amazon generic refractometer that has auto temp compensation. I used the Hanna salinity checker 35ppt calibration solution as I figured the salinity would work the same.

Depending on how Hanna made it, it would not. My DIY solutions, for example, are different for 35 ppt by refractometer and conductivity.

Spare time · Oct 12, 2023

Troylee said:
Get a plastic hydrometer and leave the fancy toys in the drawer.. it’s all I use and works fine! Instant ocean one from petco. Lol. It might be off a little but it’s consistently off so it works great! Haha

That instant ocean hydrometer is surprisingly very accurate if kept cleaned and dipped correctly.

Dburr1014 · Oct 13, 2023

Spare time said:
That instant ocean hydrometer is surprisingly very accurate if kept cleaned and dipped correctly.

Yes it is.
Mine is 10 years old. I have dropped it, don't rinse it(I do dip a few times before taking a reading) and I check it against the refractometer every 6ish months and it still gives me a perfect reading.

BubblesandSqueak · Oct 13, 2023

Dburr1014 said:
Yes it is.
Mine is 10 years old. I have dropped it, don't rinse it(I do dip a few times before taking a reading) and I check it against the refractometer every 6ish months and it still gives me a perfect reading.

I have the IO Plastic box and it reads .003 below the ATC refractory I have. been looking to get a digital one which is between the Hanna and Milwaukee.

Troylee · Oct 13, 2023

Dburr1014 said:
Yes it is.
Mine is 10 years old. I have dropped it, don't rinse it(I do dip a few times before taking a reading) and I check it against the refractometer every 6ish months and it still gives me a perfect reading.

Same haha! It’s even broke on the stand part so I gotta hold it level to get a reading

Reefer Matt · Oct 13, 2023

The calibration solution for the Hanna Salinity Tester cannot be used with refractometers. It should state that on the pouch.

Randy Holmes-Farley · Oct 13, 2023

Reefer Matt said:
The calibration solution for the Hanna Salinity Tester cannot be used with refractometers. It should state that on the pouch.

Do we know that for sure?

Some, like the American Marine/Pinpoint can because they are a seawater mimic. Others may be NaCl or KCl, and cannot.

I've looked for such info from Hanna and could not find exactly what they make the solution from.

Reefer Matt · Oct 13, 2023

Randy Holmes-Farley said:
Do we know that for sure?

Some, like the American Marine/Pinpoint can because they are a seawater mimic. Others may be NaCl or KCl, and cannot.

I've looked for such info from Hanna and could not find exactly what they make the solution from.

Yes, I am a retailer for Hanna, and had this issue before. I will upload a picture of the pouch later. The one they have listed on their site is not the current labeling. To be clear, I am speaking of the HI70024P calibration solution for the HI98319 salinity tester.

Randy Holmes-Farley · Oct 13, 2023

Reefer Matt said:
Yes, I am a retailer for Hanna, and had this issue before. I will upload a picture of the pouch later. The one they have listed on their site is not the current labeling. To be clear, I am speaking of the HI70024P solution for the HI98319 salinity tester.

Ok, thanks.

Reefer Matt · Oct 13, 2023

@Randy Holmes-Farley , here is a photo of the current packaging.

Randy Holmes-Farley · Oct 13, 2023

Reefer Matt said:
@Randy Holmes-Farley , here is a photo of the current packaging.

Ok, thanks!

Uncle99 · Oct 13, 2023

buruskeee said:
My salinity might be at 46ppt!

I used the refeactometer I just got to check against my Hanna which reads my tank at 34.5ppt. The refractometer read 42ppt out of the box.

I used 2 calibration pouches from Hanna that are supposed to be perfectly 35ppt.

Originally I tested the second calibration pouch with the refractometer and it read 30ppt.

I calibrated twice - both the Hanna checker and the refractometer.

Now my tank water reads 46ppt with the refractometer and 34.8ppt with the Hanna.

I don’t want to make drastic changes to my water in the meantime - what do you all recommend until I can get to check against someone else’s tank water and their testers?

Same problem for me.
Same for my LFS. Lost some corals first.
Now just sits in a box.

Refractometer continues best for me. Right every time.

buruskeee · Oct 13, 2023

Reefer Matt said:
@Randy Holmes-Farley , here is a photo of the current packaging.

lol I can’t not see it on the packs now. Don’t know how I missed that! Doh!

Narideth · Oct 13, 2023

Pod_01 said:
How are the critters in the tank? If they look normal sit on your hands and do nothing today.

In the mean time get this:

No calibrations required. Turn off the flow put in tank , read the value, done.

I got this after I had a salinity issue in my tank that was revealed by, of all things, a magnesium test. I got two different inaccurate calibration fluids for my refractometer and by the time I'd tested with five different types of salinity checkers through two different LFS, my salinity ended up being somewhere around 1.017.

I found this out with the TM hydrometer and now I use it to double check my refractometer. It's also deceptively huge. It can't free float in my 13 gallon tank.