Salinity testing gone bad

Chris_from_SoCal

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I last had salt water tanks 30 years ago. I used a refactometer that I am pretty sure had no way to calibrate it.

Now I setup my reef tank 3 months ago and was relying on a refactometer to give me accurate results. I did not know they now can and should be calibrated.

I noticed recently that some of my corals were receding. At first I thought it might be my fish poking at them. Then I thought things were not right and bought a digital reader.

At first I thought I wasted my money since the readings were way too high. I was searching of a way to calibrate it but found it was factory calibrated and should not need to be redone. When searching for this I found out my manual refractometer can and should be calibrated.

After watching a youtube video I found that my refractometer way way off and after fixing the calibration it now matches what the new digital reader was telling me.

I have been pretty good at keeping my tanks at what I thought was 1.025 but it has been actually at 1.032. Now I know better.

I am working the salinity down a bit every day so I don't cause more problems.

That sucked but at least it was fixable.
 
Back to normal.
salinity_normal.jpg
 
Make your own DIY calibration solution with table salt and RO water. Randy’s recipe is found on here and Google

Get a Tropic Marin glass hydrometer and a 500ml cylinder.

Weigh your salt. Digital kitchen scales are cheap and easy to get. Weighing salt keeps it super consistent unlike scoops and cups.
 
Make your own DIY calibration solution with table salt and RO water. Randy’s recipe is found on here and Google

Get a Tropic Marin glass hydrometer and a 500ml cylinder.

Weigh your salt. Digital kitchen scales are cheap and easy to get. Weighing salt keeps it super consistent unlike scoops and cups.

Thanks but the problem was that I was not aware that the refractometer was even adjustable. It wasn't until I bought the digital meter that something was definitely wrong. I was looking for a way to calibrate the digital one when I found a YouTube video on how to calibrate the exact refractometer I have. There was even a screwdriver in the container hidden under the pipettes.

I did see a thread about Randy's recipe in passing and was looking for it when I came across that video. The refractometer was way off and it was adjusted. It now matches up with the digital one. I do have a digital kitchen scale.

I will look at getting a hydrometer.
 
Thanks but the problem was that I was not aware that the refractometer was even adjustable. It wasn't until I bought the digital meter that something was definitely wrong. I was looking for a way to calibrate the digital one when I found a YouTube video on how to calibrate the exact refractometer I have. There was even a screwdriver in the container hidden under the pipettes.

I did see a thread about Randy's recipe in passing and was looking for it when I came across that video. The refractometer was way off and it was adjusted. It now matches up with the digital one. I do have a digital kitchen scale.

I will look at getting a hydrometer.
This is the one I would recommend getting!

https://www.bulkreefsupply.com/high-precision-hydrometer-tropic-marin.html
 
I have found I need to re-calibrate my BRS refractometer every time I use it. Sometimes it stays in adjustment for several uses, then it goes out every time I open the box. I use Randy's recipe. It's just habit now.
 

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