Best hydrometer

Bar & Wine

The temperature must be 60 degrees to achieve an accurate measurement with a hydrometer. If it is not, you will need to consult the documentation that came with your model to learn what adjustments are required to obtain accurate readings.

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Which hydrometers are best?

If you are a home brewer or a winemaker, you need certain tools to be successful. One of those tools is a hydrometer. These clever devices allow you to measure how much sugar or alcohol is in a solution. This information is vital to the home brewer.

The best hydrometers come as a kit, so you have everything you need on hand. They are also made of glass and are easy to read. Brewing America’s Hydrometer Alcohol Tester Kit is a perfect example of all of these things. It is a high-quality kit that comes with everything you need to measure your homemade adult beverages’ alcohol content accurately.

What to know before you buy a hydrometer

What is a hydrometer?

A hydrometer is a sealed tube with a weighted bottom that is designed to be buoyant. The tube typically has three scales inside, marked similarly to a thermometer. A hydrometer uses Archimedes’ law of buoyancy to determine the specific gravity of a solution. In short, how deep the hydrometer sinks determines how much sugar is in the solution.

When do you use a hydrometer?

There are two key moments when you use a hydrometer. The first time is before the fermentation process begins. This is when there will be the greatest amount of sugar in your wort, because it hasn’t been turned to alcohol yet. The second time is at the end of the fermentation process.

You use the “potential alcohol by volume” scale on your hydrometer when checking for alcohol content. The difference between the two readings tells you your alcohol by volume. If the wort starts at 7% and ends at 2%, that means you’ve just crafted a beer that is 5% ABV.

What to look for in a quality hydrometer

The best hydrometers are glass

While plastic is more affordable and will not break as easily as glass, any contamination can lead to inaccurate measurements. Since glass is non-porous, it is a better hygienic option, especially in matters where cleanliness is essential. Plastic is not a deal-breaker when it comes to hydrometers, but glass is a better option.

Includes a testing tube

Besides the hydrometer, you need a testing container. The ideal size is small and narrow because the less wort you use during testing, the better. This item will look like a large test tube that stands on its own. If the hydrometer you purchase does not include this item, and you do not already have one, you will need to purchase one separately.

Has a case

A hydrometer is a fragile glass tool. If your purchase includes a protective case, there is less chance the hydrometer will break in storage.

Easy to read

The dashes and numbers on a hydrometer are small, making them difficult for some to read in even the best conditions. A hydrometer that is easy to read will lead to fewer reading errors.

Cleaning brush

To keep your testing tube clean, you will need a small bottle brush. If your hydrometer comes with this item, it will be appreciated.

How much you can expect to spend on a hydrometer

You can get a hydrometer without a testing container for less than $10. If you need all the components, an entire testing kit that includes the hydrometer, a testing container, a brush, a case and more may cost up to $30.

Hydrometer FAQ

Is it hard to use a hydrometer?

A. No. It is very easy to use a hydrometer. If you know how to put a straw into a drink, you already know how to use a hydrometer. First, you will need to fill your hydrometer test container with wort. You do not need to fill it to the top. It just has to be deep enough to allow your hydrometer to float freely inside. Next, gently place the hydrometer in the test container, lower it until you start to feel some resistance, then let it go. When the hydrometer becomes steady, look at where the fluid plane lines up on the hydrometer to get a reading.

Are there any tips or tricks for getting the best reading?

A. To obtain an accurate reading, there can be no bubbles in your liquid. Make sure you carefully fill your testing tube by allowing the wort to run down the side, so it doesn’t create bubbles. If you do get bubbles, you can gently stir the wort to help free them. Also, it can help give the hydrometer a gentle spin to make sure it isn’t sticking to the side of the testing container. Alternatively, you can push the hydrometer down into the wort about .5 inches beyond where it naturally floats and let it bob back to the surface and settle before taking a second reading to verify the first was accurate.

What are the best hydrometers to buy?

Top hydrometer

Brewing America Hydrometer Alcohol Tester Kit

Brewing America Hydrometer Alcohol Tester Kit

What you need to know: This kit may cost a little more than other options, but it has quality components and includes everything you need.

What you’ll love: This triple-scale hydrometer is designed for use in wine, beer, cider and mead. Purchase includes a glass testing tube as well as a bottle brush. The compact design of the testing jar means you do not waste as much product when testing. It only requires 125 ml.

What you should consider: This model is on the higher end of the price scale, but you are paying for a quality product.

Where to buy: Sold by Amazon

Top hydrometer for the money

Brewer's Elite Hydrometer Test Jar Kit

Brewer’s Elite Hydrometer Test Jar Kit

What you need to know: If you like to stretch your dollar, this comprehensive testing kit features many components that make it a solid purchasing option.

What you’ll love: This hydrometer testing kit comes with a triple-scale hydrometer, a testing jar, a cleaning cloth, a cleaning brush, a bag and a storage case. For peace of mind, this kit also comes with a money-back guarantee.

What you should consider: A few users thought this model was difficult to read.

Where to buy: Sold by Amazon

Worth checking out

Home Brew Ohio Hydrometer

Home Brew Ohio Hydrometer

What you need to know: If you are on a tight budget, this basic model will suit your needs.

What you’ll love: This hydrometer is easy to read and comes with the instructions needed for testing beer and wine. It arrives carefully packaged to reduce the chance of breakage during shipment and includes a temperature conversion chart.

What you should consider: This hydrometer doesn’t come with a test jar, but it is highly affordable.

Where to buy: Sold by Amazon


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