What factors affect a hydrometer

[komomos]

I have an almost finished beer in the carboy. But hydrometer points quite high (1,034)

Does only sugar contain affect a hydrometer?

 

[bad67z]

Temperature will also effect your reading. Take a look at your hydrometer, on it should be listed the temperature that it is calibrated. In my experience most are calibrated @ 60 deg F.

 

[Brewnoob1]

Does it taste sweet? If so, it's probably the sugar that is affecting it. But temp as well as co2 in solution can affect it.

 

[dbhokie]

Hydrometers are calibrated to weigh particulate matter in solutions. The one's we use are calibrated to measure saccharides in a solution. As mentioned temperature and CO2 can throw off hydrometers, (mainly the bubbles clinging to it in a test sample, just degas the sampling). Other than that most of the errors relate to user, not equipment.