Hydrometer or refractometer

[tahoetavern]

I am able to borrow a refractometer from work when I need it. Should I still invest in a hydrometer? Or use the refractometer from work until I by one of my own?

 

[gpack]

IMO, you will always need both.

The refractometer will be a huge help when sparging, but won't be the tool you will want when taking FG as they don't give correct readings when there is alcohol in the mix.

 

[CastleHollow]

Refractometers are mostly useful on brew day when doing all grain. Hydrometers are useful all the time. Given the measurements you should be taking during the brewing process, I would suggest getting a hydrometer first.

 

[unionrdr]

Yeah,I bought a couple hydrometers right off the bat. I figured it best to have a back up one in case one got broken. I was right,of course.

 

[Evan_L]

IMO, you will always need both.

The refractometer will be a huge help when sparging, but won't be the tool you will want when taking FG as they don't give correct readings when there is alcohol in the mix.

Please explain....

 

[Yooper]

Please explain....

Refractometers are great when sparging, to check and see if your runnings are getting too low (under 1.010). They are also important for checking preboil gravity.

I use a refractometer pre-fermentation, but a hydrometer after that. If I was not doing AG brewing, I wouldn't bother with a refractometer as they aren't needed for extract brewing.

 

[jeremy0209]

^^^^this^^^^

I'm also in the 'you need both' camp. I use my refractometer to check preboil gravity as well as OG, but my hydrometer has the last word regarding FG.

 

[tahoetavern]

This will be my first batch, it is the carabou slobber ale from NB. don't want to waste money on equipment if I don't have to. Can someone break down how they are different? I could just google it of course but I like hearing from you guys.

 

[mtnagel]

I only use my refractometer and I use it after fermentation has started. Yes I know the number is wrong, but I use the online calculators to correct for the alcohol. I know someone posted that this matched their hydrometer. Even if the corrected number is off by I few points, I don't care.

I use it to know that fermentation is completed before bottling or moving to secondary.

And FYI, if your refractometer is a dual scale (brix and SG), make sure the scales line up. The $30 one I bought on Amazon didn't match up using conversion calculators so I checked my refractometer with sugar solutions (see this post) and the brix side is accurate, but not the SG side, so now I only use the brix side.

I use it to know that fermentation is completed before bottling or moving to secondary. use it to know that fermentation is completed before bottling or moving to secondary.

And FYI, if your refractometer is a dual scale (brix and SG), make sure the scales line up. The $30 one I bought on Amazon didn't match up using conversion calculators so I checked my refractometer with sugar solutions (see this post)nd FYI, if your refractometer is a dual scale (brix and SG), make sure the scales line up. The $30 one I bought on Amazon didn't match up using conversion calculators so I checked my refractometer with sugar solutions (see this post)

 

[unionrdr]

A refractometer can measure the amount of sugar in the wort,& thus pre-boil gravity. But it's useless beyond that when alcohol is present. Then you need a hydrometer,which measures gravity changes as the sugar gets turned into alcohol.

 

[mtnagel]

This will be my first batch, it is the carabou slobber ale from NB. don't want to waste money on equipment if I don't have to. Can someone break down how they are different? I could just google it of course but I like hearing from you guys.

Refractometer:

• uses a couple drops so you waste less beer
• alcohol screws up the reading, so if you use it after fermentation has started, you need to correct for that
• more expensive than hydrometer upfront, but less fragile so it will be cheaper in the long run

Hydrometer:

• cheaper but more fragile (you will break them)
• uses more beer for a reading
• can use after alcohol is present

 

[Yooper]

This will be my first batch, it is the carabou slobber ale from NB. don't want to waste money on equipment if I don't have to. Can someone break down how they are different? I could just google it of course but I like hearing from you guys.

Keep in mind that a refractometer isn't helpful with extract brewing, so if you are making extract batches as a beginning, it really isn't of any benefit to you at all.

 

[msa8967]

I don't want to hijack the original question in this thread but I would like to know which of these two refractometers would brewer's recommend.

http://www.ebay.com/itm/RSG100ATC-B...t-SG-032-Refractometer-SOFTCASE-/220976517877

http://www.ebay.com/itm/BREWfractom...G-Beer-Brew-Refractometer-Plato-/221206107131

 

[Yooper]

I don't want to hijack the original question in this thread but I would like to know which of these two refractometers would brewer's recommend.

http://www.ebay.com/itm/RSG100ATC-B...t-SG-032-Refractometer-SOFTCASE-/220976517877

http://www.ebay.com/itm/BREWfractom...G-Beer-Brew-Refractometer-Plato-/221206107131

Mine seems to be most like the first one but without the the "sg" scale on the right (which is pretty useless anyway).

 

[msa8967]

Mine seems to be most like the first one but without the the "sg" scale on the right (which is pretty useless anyway).

So will multiplying the Brix reading by 10 will give you a better reading for the gravity than using the SG scale shown on the right?

 

[Gduck]

Yeah,I bought a couple hydrometers right off the bat. I figured it best to have a back up one in case one got broken. I was right,of course.

I wish they sold them in multi-packs. I've only broken a couple, but sometimes I'm a bit of a klutz when it comes to clean up time.

Also I like having a second one around in case I get a reading that has me scratching my head so I can use a second hydrometer to check the reading. I've had the paper slide down in one of the hydrometers I had so it was giving me bogus readings.

 

[msa8967]

I have had 3 of my 6 hydrometers suffer from the paper sliding down without me being aware of it. Might be time to buy a refractometer at the cost of 3-4 hydrometers.

 

[unionrdr]

I've been lucky with this one,my 2nd. I've had it since day one. I started using it like a year later. I was holding the skinny end washing it & shook it dry. Oops. This one's working great,so I'll just stick with it.

 

[sfgoat]

I can't stop breaking my hydrometers so I just gave up on them. I use a refractometer and when taking FG I just plug my numbers in here: http://onebeer.net/refractometer.shtml and its been pretty accurate for me.

 

[ianw58]

This will be my first batch, it is the carabou slobber ale from NB. don't want to waste money on equipment if I don't have to. Can someone break down how they are different? I could just google it of course but I like hearing from you guys.

As brewers, we want to know how much sugar is dissolved in water. We need to know this to be able to understand when fermentation is complete, calculate alcohol content of our beer, understand the extraction of sugars from our mashed grains, etc.

Although there are many other compounds in the wort, we neglect most of these and assume that the increase in density of our wort is due to sugars alone.

A hydrometer measures the density of a liquid relative to another liquid. In our case, we want to know the density of our wort relative to water. The scale we use mostly sets the density of water at 1. The hydrometer floats higher in liquids that are more dense than water. For our purposes, the increase in density due to sugars being dissolved in water is pretty linear.

A refracts enter takes advantage of the fact that light refracts or bends as it moves from air through a liquid. This is why sticks stuck in water look as though they bend at the water's surface. It turns out that the AMOUNT of this bending changes when the density of the liquid changes. Again, for our purposes and sugar concentrations, the scale is pretty linear.

Unfermented wort is, for gravity purposes, whether a hydrometer or refractometer is used, sugar dissolved in water. Yes, there are lots of other compounds in thereto, but, they add relatively little to the density number. We have just one variable to consider: the amount of sugar dissolved in water.

Once the wort starts fermenting, the liquid is a combination of water AND alcohol. Now, we have two variables to consider: the amount of sugar dissolved in water and the amount of alcohol dissolved in water. The increase in alcohol and the decrease in sugar is not linear, as far as refraction is concerned. It IS relatively linear as far as density is concerned, however.

In summary, when there is only sugar and water, either method, refractometer or hydrometer, works well to measure density of the wort. Once fermentation begins, there are too many variables to measure density by refraction of light through the sample.

While it is and important part of brewing to understand the gravities of our wort, pre-boil, post-boil, during fermentation and after fermentation is finished, the all grain brewer wants to know gravities during sparging as well. Gravities measured during sparging will tell the brewer when the extraction of sugars from the grain is completed. As Yoopers pointed out, continuing to rinse the grains when the running gravity has dropped below 1.010 can lead to rinsing out things we don't want in our wort, such as tannins. The refractometer provides a quick method of determine these gravities. Since the extract brewer isn't rinsing grains, fast measurements on the fly are not needed and the refractometer is of little value.

 

[tahoetavern]

holy crap Batman... You know your stuff! That was awesome. any advice on which hydrometer then? Seems like everywhere I look, people are complaining about broken or faulty hydrometers. Thanks again

 

[unionrdr]

This one is pretty darn close to the glass ones I used to get from Cooper's; http://www.midwestsupplies.com/hydrometer-triplescale.html
But they also have this pro model for $55; http://www.midwestsupplies.com/pro-model-precision-thermohydrometer-by-alla.html
NB also has this for the base of the common size hydrometer storage tubes many of us test in; http://www.northernbrewer.com/shop/brewing/brewing-equipment/testing-measuring/foam-hydrometer-stand-ring-blue.html A real bargain @ $1.60 for something so handy!

 

[Yooper]

So will multiplying the Brix reading by 10 will give you a better reading for the gravity than using the SG scale shown on the right?

No, but it's a good guestimate to go with until you are done brewing and can sit down with your software or spreadsheet.

don't forget to calibrate your hydrometer with your refractometer, to get your brix correction factor!

 

[NadoHawk]

I don't want to hijack the original question in this thread but I would like to know which of these two refractometers would brewer's recommend.

http://www.ebay.com/itm/RSG100ATC-B...t-SG-032-Refractometer-SOFTCASE-/220976517877

http://www.ebay.com/itm/BREWfractom...G-Beer-Brew-Refractometer-Plato-/221206107131

Yeah. I've been looking at those two as well...almost a 40 USD difference between the two.

The cheaper one has this disclaimer.

INACCURACY OF THE RSG-100ATCc TO BE AWARE OF! (a disclaimer)

Inaccuracy? What? Yes. This is the disclaimer that you should read before you buy. The other guys don't post this because they don't know any better! They just sell "stuff"...

Please be aware that this unit and the other cheap units sold on eBay have an internal flaw. What's the flaw? The Wort SG scale gradually becomes inaccurate the higher you go.

When the scale was conceived, it was done so using a simple formula - % Brix x 4 = Wort SG. For example, 10% Brix x 4 = 1.040 Wort SG, which is somewhat accurate. Move it out to 20% Brix and you have a problem - 20% x 4 = 1.080 Wort SG, but it's really 1.084 Wort SG! The scale becomes more in accurate the higher you go! Making an Strong American Ale or a Double IPA? Using this unit (RSG-100ATCc) could cause problems with higher gravities!

So the cheaper ones aren't nearly as accurate as a hydrometer right off the bat and especially not accurate for non-conversion FG readings.

Anyone know how accurate their description of cheap refractometer readings are for high-gravity brews and whether a simple calculation would correct the discrepancy. I don't want to pay more for something I can easily calculate with a new formula.

 

[Yooper]

Yeah. I've been looking at those two as well...almost a 40 USD difference between the two.

The cheaper one has this disclaimer.



So the cheaper ones aren't nearly as accurate as a hydrometer right off the bat and especially not accurate for non-conversion FG readings.

Anyone know how accurate their description of cheap refractometer readings are for high-gravity brews and whether a simple calculation would correct the discrepancy. I don't want to pay more for something I can easily calculate with a new formula.

ALL refractometers have that same "flaw".