Refractometer?

[smomus]

I am going to start changing my gsp tank over to brackish. I am looking at the refractometers on ebay and amazon because they are much cheaper! Anyway is there anyone that will recommend a specific brand or model number? Any that I should stay away from?
I do have the hygrometer, but quickly learned that it wont go low enough to raise the salinity by .002 sg per week so at this point it is basically useless!
Thanks!

 

[fort384]

I have one of these: Refractometer for reading salinity w/ Free Calibration fluid - English

And it works very well. You would easily be able to measure 0.02 per week on it from 1 up to whatever value you are headed for.