Originally Posted by ajdelange
Stick with the hydrometer. In brewing refractometers are great for monitoring the decline in extract as sparging proceeds but they really aren't good for much else.
Actually, they are also very good for determining when fermentation is complete for those people who feel the need to take gravity samples on a daily basis. When the Brix stops dropping, fermentation is complete. Then, you can take a single gravity reading to find out what the FG really is, leaving you with a lot more beer to drink than if you had taken multiple hydrometer samples.