Refractometer calibration

[PeterEde]

Can I use sea water to calibrate my meter. Given the average NSW salinity is 35ppt
Can I use RODI to calibrate for ZERO
I would prefer to use Hanna cal but getting one may prove difficult

 

[EeyoreIsMySpiritAnimal]

If you look at the sticky threads in this forum, the last one has an article about how to make refractometer calibration fluid.

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

 

[Gtinnel]

Agreed its easy to make your own with rodi water and table salt. You should calibrate to close to the salinity of the water you're testing.

 

[Velcro]

Calibration solutions are cheaper than worrying about how accurate your kitchen scale is

 

[EeyoreIsMySpiritAnimal]

Calibration solutions are cheaper than worrying about how accurate your kitchen scale is

If you read Randy's article, it explains that most kitchen measuring spoons/cups are accurate, and he gives a formula to make a 3.65 weight percent solution.

 

[PeterEde]

If you look at the sticky threads in this forum, the last one has an article about how to make refractometer calibration fluid.

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

You know what I saw that and forgot about it. Thanks

 

[PeterEde]

Calibration solutions are cheaper than worrying about how accurate your kitchen scale is

If I can find one locally
I looked for Hanna salinity cal fluid. Only found ebay store in UK

 

[EeyoreIsMySpiritAnimal]

If I can find one locally
I looked for Hanna salinity cal fluid. Only found ebay store in UK

If you don't want to go the DIY path, just figure out what ppt the Hanna fluid is and try to find another brand/ manufacturer.

 

[Dolphins18]

calibration solution is 5 dollars on amazon. I love diy, but sometimes amazon is just easy. This is one of those times.
Amazon product

 

[EeyoreIsMySpiritAnimal]

calibration solution is 5 dollars on amazon. I love diy, but sometimes amazon is just easy. This is one of those times.
Amazon product

Agreed. Love Amazon

 

[PeterEde]

I have a good LFS on my way home from work who sells Hanna checkers. Hopefully they have the fluid.
Otherwise Amazon
Thanks every one

 

[Gtinnel]

Calibration solutions are cheaper than worrying about how accurate your kitchen scale is

If you scale up the recipe for Randy's diy calibration solution 10x then small measuring differences with scales won't matter. Sure you make way more solution than you need, but it still costs essentially nothing to make. I also trusty own solution much more than bought solutions.

@PeterEde what refractometer are you using?

 

[Neon_Devil]

I had a refractometer for years and dealt with the calibration solution issue. I recently bought the Hannah salinity tester and I love it. It's pricy but what isn't in this hobby. It also reads the water temp at the same time. I would recommend this item to everyone

Amazon product

 

[happyhourhero]

I calibrate mine with my hydrometer

 

[Gtinnel]

I had a refractometer for years and dealt with the calibration solution issue. I recently bought the Hannah salinity tester and I love it. It's pricy but what isn't in this hobby. It also reads the water temp at the same time. I would recommend this item to everyone

Amazon product

I have that also and ironically I hate it. It's convenient to use, but my reading jumps around all over the place. It doesn't always settle on one value.

 

[PeterEde]

If you scale up the recipe for Randy's diy calibration solution 10x then small measuring differences with scales won't matter. Sure you make way more solution than you need, but it still costs essentially nothing to make. I also trusty own solution much more than bought solutions.

@PeterEde what refractometer are you using?

Aquamedic

 

[PeterEde]

I had a refractometer for years and dealt with the calibration solution issue. I recently bought the Hannah salinity tester and I love it. It's pricy but what isn't in this hobby. It also reads the water temp at the same time. I would recommend this item to everyone

Amazon product

$75 US it's $140 in Australia

 

[PeterEde]

I have that also and ironically I hate it. It's convenient to use, but my reading jumps around all over the place. It doesn't always settle on one value.

Sounds faulty

 

[Neon_Devil]

I have that also and ironically I hate it. It's convenient to use, but my reading jumps around all over the place. It doesn't always settle on one value.

That's a bummer. I found it a hassle dealing with the refractometer. As long as we all get 1.026 right?

 

[Gtinnel]

Aquamedic

I'm not sure with store bought solutions but I know with the diy ones the solution to calibrate a refractometer is not the same as the one to calibrate a conductivity probe/tester. I'm not sure if Hanna sells a solution for refractometers but I don't think you can use the one they sell for conductivity for a refractometer.

Basically just make sure you are using the right solution for your device (again I'm assuming there is a difference on store bought solutions).