Most people prefer refractometers.
Problems exist for both refractometers and hydrometers. In a recent test, I found the hydrometer I use to brew beer is more accurate than the refractometer I use for my reef. I would get a refractometer and calibrate it once a year.
When this happens, how fast do you lower salinity? I have heard people say to get back to 1.025 (or whatever is normal for you) as fast as possible, and others say to lower by no more than 0.0005 a day.