Salinity calibration liquid discrepancies

[boboyo]

I’m about to do hyposalinity to treat my whole tank and it seems like all calibration juices are off!!! They all say they’re 35ppt. Calibrated with the reagents brand I have

1.021 with Hanna calibration
1.029 with accurasea

Is there a way to get a real calibration? I don’t want to mess this up and the discrepancies are huuuuge if you look at hanna

 

[boboyo]

I shook them all very very well, used different pipettes. My digital Hanna reader reads the same as my current refractometer if they’re both calibrated on the same liquid. (I bought the Hanna so it can read under 1.015)

 

[Hermie]

from my understanding you have to match the calibration liquid to the instrument you're calibrating, so not all refractometers use the same liquid, and if it's a hydrometer it may need a different liquid

 

[Hermie]

See, one of those things you have says "not for use in refractometers"and the other says "refractometer"

 

[boboyo]

the Hanna being calibrated with Hanna reads my tank at 1.022 while my refracto said 1.026 before topoff

 

[Hermie]

And what exactly did you calibrate the refractometer with? My refractometer has to be calibrated with 0.0 ppt water

 

[boboyo]

And what exactly did you calibrate the refractometer with? My refractometer has to be calibrated with 0.0 ppt water

35ppt solution. Mine doesn’t read anything below 1.018

 

[Hermie]

35ppt solution. Mine doesn’t read anything below 1.018

not all 35ppt solutions are created equal, what exactly was the 35 ppt solution? and is that what the instructions say to use to calibrate your refractometer with? both of those answers are important to figuring this out

 

[boboyo]

So mine is the regular ATC one, got it secondhand in a h2ocean box but it barely fits so not sure if it’s that. No brand is written on the réfractomètre itself.

i tried the accurasea solution and the Hanna liquid at my LFS on a fancy big Hanna machine and got 1.028 and 1.027 for accurasea and 1.019 for the Hanna. They have their own calibration solutions they use. Could it be the batch is faulty? I think it’s more of a calibration juice issue rather than a brand because 35ppt should be 35ppt.... it’s a measurement of salt.
I assume they wrote not for refractometer use because it’s a pouch and if you leave it sitting water will evaporate and it won’t be accurate anymore. Assuming you can use it 30 times to calibrate a refractometer.

Just wondering if anyone has a few different brands of supposedly 35ppt and have different results

 

[Hermie]

So mine is the regular ATC one, got it secondhand in a h2ocean box but it barely fits so not sure if it’s that. No brand is written on the réfractomètre itself.

i tried the accurasea solution and the Hanna liquid at my LFS on a fancy big Hanna machine and got 1.028 and 1.027 for accurasea and 1.019 for the Hanna. They have their own calibration solutions they use. Could it be the batch is faulty? I think it’s more of a calibration juice issue rather than a brand because 35ppt should be 35ppt.... it’s a measurement of salt.
I assume they wrote not for refractometer use because it’s a pouch and if you leave it sitting water will evaporate and it won’t be accurate anymore. Assuming you can use it 30 times to calibrate a refractometer.

Just wondering if anyone has a few different brands of supposedly 35ppt and have different results

I have the same refractometer and it says to calibrate it with 0.0 solution

 

[boboyo]

The one at the lfs looked like this

Hanna HI96801 Digital Refractometer for Brix Analysis in Food

Hanna HI96801 Digital Refractometer for Brix Analysis in Food. Great savings PLUS Free Shipping when you buy now from ITM.com. In stock, fast shipping!

www.itm.com

 

[boboyo]

I have the same refractometer and it says to calibrate it with 0.0 solution

I guess I’ll try that. I see the 0 line. What do you use? Is distilled water ok?

 

[Hermie]

I guess I’ll try that. I see the 0 line. What do you use? Is distilled water ok?

distilled yeah, I use RODI

 

[boboyo]

distilled yeah, I use RODI

Both distilled and rodi read 0 when I calibrated to 0

now : accurasea is at 34.5pp
Reagents is at 31ppt
Hanna at 24 ppt

now both the Hanna and the refractometer read 1.022 on my tank. At least I have the same result (Hanna switching between 1.022-1.023 and refractometer is at 1.0215). This is an ok range for me.
Hanna reads 1.027 in the Hanna pouch. I find it pretty weird because it’s a measurement of salt and don’t see how and why my refractometer would read it differently and why a drop of it on a Hanna fancy machine would read 1.019.
At least my issue was solved. Thank you for your time