If you have one of our kits or refills, remember that isn't necessary to use the hydrometer, as our brewers measure the initial and final density of the must in all recipes. If you have already become a master homebrewer, you may want to use this test tube and the hydrometer.
Do you know what a hydrometer and test tube are used for?
We can use it to know the initial density before the must begins to ferment. In the same way, we can know when the fermentation has finished completely by measuring the final density.
In addition, since beer styles tend to be defined initial and final densities, we can know if we have achieved the beer style we were looking for. And we can also know the alcohol content we have obtained.
But remember, if you're just starting to brew beer, you don't need to use it, for the reasons we've indicated. Use it once you have made several elaborations so that you can continue learning and improving as a homebrewer.