SPR
Well-Known Member
I have been using this piece of kit since my first tank in February 2016 and trusted it completely. I am new to aquariums so bought what I believed to be the best.
Recently the readings have been fluctuating wildly. I had been maintaining salinity at 35ppm and all other parameters were spot on for my new tank or at least I thought. I had initially put this down to high temperatures here in the UK and the tank is currently at around 28-29C
The salinity readings have gone from consistent with minor fluctuations to a sudden apparent drop from 35ppm to 25ppm 3 days which led me to dump a load of salt into the tank to bring it back up.
I then start reading on the Internet about these and calibrate the Refractometer with RODI to 0 and when I test the water is 44ppm+! So been changing water to bring it back down. Fortunately or hopefully no harm has been done as I did it slowly.
Over the last few days I have been using the Refractometer and before each use checking back to 0 with RODI and I find that I have to adjust it on virtually every check to get it to read 0. I have read reviews etc and many seem to have the same problem with this. It will also vary by maybe 1 ppm with 2 consecutive tests
Any comments or experience would be greatly appreciated ? I know it's sold as a precision piece of kit but it won't seem to hold its calibration... Now I am aware of this I can deal with it but..
Recently the readings have been fluctuating wildly. I had been maintaining salinity at 35ppm and all other parameters were spot on for my new tank or at least I thought. I had initially put this down to high temperatures here in the UK and the tank is currently at around 28-29C
The salinity readings have gone from consistent with minor fluctuations to a sudden apparent drop from 35ppm to 25ppm 3 days which led me to dump a load of salt into the tank to bring it back up.
I then start reading on the Internet about these and calibrate the Refractometer with RODI to 0 and when I test the water is 44ppm+! So been changing water to bring it back down. Fortunately or hopefully no harm has been done as I did it slowly.
Over the last few days I have been using the Refractometer and before each use checking back to 0 with RODI and I find that I have to adjust it on virtually every check to get it to read 0. I have read reviews etc and many seem to have the same problem with this. It will also vary by maybe 1 ppm with 2 consecutive tests
Any comments or experience would be greatly appreciated ? I know it's sold as a precision piece of kit but it won't seem to hold its calibration... Now I am aware of this I can deal with it but..
Last edited: