Refractometer Calibration Debate

[Luke.]

Well
What do you guys do ??

since I personally got in the hobby I’ve always used rodi , never thought about it much really .. until now lol , I read some stuff and start to think, it’s probably not Good to do ,

what do you guys do / what product has been good for you ?

 

[Pistol]

Been down that road, tried all the fluids only to find they all read different and were a waste of money, Rodi water is accurate all the time, hell, tap water works to. Poured all the fluids down the drain.

 

[Luke.]

Been down that road, tried all the fluids only to find they all read different and were a waste of money, Rodi water is accurate all the time, hell, tap water works to. Poured all the fluids down the drain.

ok , so just drops of rodi , and adjust to 0? Then good to go right

 

[Matt1997]

I make my own with Iodized salt and RODI water. 3.65g salt in 96.35g water gives 1.026 sg. I now use 3 different methods. I use two conductivity probes (Hanna and salinity pen) within freshly mixed saltwater as well as a refractometer. I test all 3 prior to adding to the system.

 

[Pistol]

Ya just a few drops of rodi and calibrate to 0 and good to go, don't over complicate it.

 

[TORX]

Actual salinity is not really key, stability is key. If your refractometer fluid is off slightly as long as you use the same test method then everything is fine. I normally use RODI and it is pretty close. There is no really issue between 1.026 and 1.027 if calibration is slightly off. If you are adamant about being perfect, then your best calibration bet is to get one that is 35ppm and calibrate to it.

 

[Luke.]

Thanks everyone for your 2 cents

 

[joshthebox]

Don't calibrate with RODI. You need to calibrate with a reference solution that's close to what level your testing for. In this case you need to use a solution that has been lab tested to a salinity of 1.026. TwoLittleFishies and Brightwell both sell a product for that I believe. Calibrating with RODI won't give you an accurate result at all. I use this one personally https://www.aquariumdepot.ca/brightwell-aquatics-refractometer-calibration-standard-60ml.html

 

[Pistol]

Don't calibrate with RODI. You need to calibrate with a reference solution that's close to what level your testing for. In this case you need to use a solution that has been lab tested to a salinity of 1.026. TwoLittleFishies and Brightwell both sell a product for that I believe. Calibrating with RODI won't give you an accurate result at all. I use this one personally https://www.aquariumdepot.ca/brightwell-aquatics-refractometer-calibration-standard-60ml.html

Calibration fluid is shit, I've purchased several kinds and they are all different, anywhere from .023 to .028
tap water is better.

 

[Luke.]

Yeah such a hit and miss , damned if you do and damned if you don’t..

 

[Pistol]

I also have a milwaukee digital and it is calibrated with rodi water as per the instructions and it is accurate as well and reads the same as my refractometer when calibrated with rodi