Refractometer. I need help.

Gene1948

Dear colleagues! For all these years, I have been measuring the salinity of water using a hydrometer. Recently, I purchased an AquaMedic refractometer with ATC. I also bought a calibration solution, Salit, for adjusting refractometers. I decided to check the factory settings of the device with the solution. I followed the instructions: I shook the calibration solution, placed a few drops on the glass slide, closed the lid, and waited for about 30 seconds. The salinity reading was 40 parts per thousand. I adjusted it with the screw. The next day, I decided to repeat the same procedure. This time, the salinity of the calibration solution was 33 parts per thousand. I adjusted it again. In short, I have repeated this procedure about 10 times, and each time the result is different. Am I possibly doing something wrong?

Natasha7622

Do you wash the glass pieces well? They suggest making you another test solution (a small jar) of arbitrary concentration. Try to take readings from the factory-made one and the one you made.

Megan

I think I wipe well. The instructions say that washing is not allowed. Only wiping. What will a new solution give if the current one shows different values each time? I also tried osmosis. That's what the refractometer instructions recommend. In fact, the first time I tried deionized water. The result was less than 0.

Debra

The new solution will provide that if it makes an error at the factory every time, it would have the same error on the second one as well.

Brenda

There is a suspicion that the lenses (parts affecting the measurements) are poorly secured. And with each new measurement, they show different values due to their displacement. Try to take more measurements but with minimal vibrations and movements of the refractometer. In other words, make it stationary for several measurements.

Alan273

I read a bit here and there. I'm starting to understand that I need to give myself a break. I suspect that from the very beginning, I messed up the refractometer's calibration when I started adjusting it at different temperatures and with different solutions. So, I'll try to start fresh: I'll calibrate it with deionized water at 20°C, which was its factory setting. That's what the instructions say. After that, I'll see what happens.

Michelle9986

Try... But if the error keeps jumping on the established substance, then I have some doubts...

Mary

The glass itself can be cleaned; if it is not cleaned, salt dries on it, and when a new measurement is taken, the droplet dissolves that salt, causing the refractometer to show a higher salinity.

Frank7213

I wonder how things are going with the refractometer?

Lee425

I contacted the manufacturer, Aquamedic. I explained the situation. They agreed that the device was not functioning correctly. Therefore, I returned it to the seller.