How To Use A Hydrometer

Everyone wants to make good beer, cider, wine and spirits, however it is not only about using quality
ingredients. Sanitising, racking to a secondary fermenter, and taking hydrometer readings all help ensure a better
end result.

Of these, the hydrometer reading is the most skipped process by home brewers. It may be a worry that it is difficult or maybe simply not a useful resource.  Either way, not taking a hydrometer reading is a huge mistake!

A hydrometer, by definition, is a sealed graduated tube containing a weighted bulb, used to
determine the specific gravity or density of a liquid.  For home brewing and distilling, the purpose of this
device is to measure the amount of sugar in a solution which can be converted into alcohol.
Hydrometer readings should be recorded both before and after fermentation.

Taking A Hydrometer Reading
1. Sanitise all equipment that will come in contact with your beer, cider, wine or wash.
2. Take a sample of the liquid before you add the yeast.
3. Place the sample in a hydrometer test jar. If you have a sampler or pipette, you do not need to do
this as the sampler or pipette doubles as a test jar.
4. Spin the hydrometer to remove any bubbles that might be clinging to it.
5. With the sample at eye level, look to see where the liquid crosses the markings.
6. Write down the reading. This is your starting gravity (SG). Check your recipe to see what the
proper original gravity (OG) range is for your kit and make sure it is in that range.
7. Let the beer, cider, wine or wash ferment completely and then take a reading again after
complete.
8. Write that number down. This your final gravity (FG).
9. The equation to figure out the amount of alcohol is this: (Starting Gravity – Final Gravity) x 131.25.
Example;
S.G. 1.050 – F.G. 1.010 = 0.04
0.04 x 131.25 = 5.2% ABV
10. Alternatively, there are a multitude of online calculators you can use by inputting the readings.  Just do a search in your chosen search engine!

Chris Marshall – brewathome.shop (Last Updated: 27th September, 2022)