Hydrometer

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cuz

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I bought a new hydrometer. I tested water with it but it doesn't read .99. I used sink water, spring water and distilled water and all got the same reading at almost 1. I enclosed a picture. I am debating whether to send it back or just make the adjustment when using it. Did anyone else have this issue?

Hydrometer.jpg
 
With distilled water it should read 1.0 for the sg, which also would be 0 for the brix scale. The temperature would also have a small effect depending on the calibration temp of the hydrometer.
 
So can anyone tell me if this hydrometer is accurate?
 
That is as accurate as any triple scale inexpensive hydrometer. And it's enough since what really matters is relative vs absolute measurements.

If you really want to know, you'll have to buy some calibrated short scale hydrometers. I have +5/-5 for the end for fermentation and +19/+31 for the start. Much more accurate, much more expensive. But the +5/-5 is really a joy at the end of fermentation. It's easy to read, accurate and very helpful. These are the 2 that I have, plus I have a triple scale too for quicky measurements when I'm just trying to see that fermentation is proceeding.

https://www.amazon.com/gp/product/B00557ZX64/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&th=1
https://www.amazon.com/gp/product/B00551PGA8/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&th=1
 
Based on that image it appears to be reading incorrectly. Unless your water has a significant amount of alcohol in it, the reading for tap water or distilled water should be much closer to 1.000. That looks like a reading of about .994
If you run a temperature correction for a hydrometer you will find the difference is really pretty small, especially at what should be reading of 1.000

Here's a rather extreme example - Hydrometer calibrated for 68 f but assuming the water is actually 90 f The difference is only .003 (Reality is actually Higher in this case but still not what you have there)
1603413955422.png

Here's one going the other direction Same 68 degree calibration but now assuming the water is actually 40 degrees, which would be pretty insane
The difference is only .001. (Correct reading is actually a hair lower.)
1603414203715.png

Finally Let's try the reading I see on your hydrometer of .994 and lets assume the water temp is actually 60 degree which might happen in a cool basement this time of year.
1603414350943.png

Bottom line - send it back. That a significant difference that even extreme temperature would create.

This little 'demo' is one reason I don't worry about temperature adjustments for hydrometer readings. I'd be more concerned with CO2 bubbles distorting a reading on a fermenting wine than anything temperature differences would create.
Sorry this was so long.
 
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So do any of these inexpensive hydrometers work well or do I need a $35 one like CDREW suggested? Should the reading be accurate or just in the ballpark to get a relative idea where you stand?
 
you can be anal and spend $35 for something that is .1% more accurate and only in distilled water and correct water.
the hydrometer will be placed in a liquid, not distilled water, with gases and suspended solids and varying temperature. A $35 hydrometer will not make a difference
 
I've had no problem with any of mine and they were all under $20.00. If you are concerned get a couple from one of the many good wine/beer maker supply places. AND always have at least 2 on hand. A breaking a hydrometer in the middle preparing a wine must is a disaster waiting to happen. In the middle of a ferment, it's a pain but surviveable. And above all remember "Murphy" was an optimist.
 
If you are buying the hydrometer from your local home brew store then simply ask them if they would let you check the accuracy using their tap water. It should read as close to 1.000 as dammit and if it does, it's gonna be accurate enough considering all poor reliability involved when anyone uses this instrument to take a reading - so many factors (not least temperature - but the level of the surface; the gas dissolved in the liquid; the position you are taking a reading from; the accuracy of the device itself given the viscosity of the liquids it is being asked to measure. etc
 
I've been resisting the urge to respond as I often get crabby about product quality in general. As I get older this seems to get worse.

All of my hydrometers are rather old and luckily haven't been dropped on the floor yet; they all read correctly. Distilled water should be the easiest liquid to measure, so if the hydrometer isn't accurate with that, it raises questions about the manufacturer and supplier. Many products are now supplied by "front" companies that never see or test the product, bulk loads are purchased by a third party e-commerce order fulfillment center that handles everything. Everyone has to determine if the instrument quality and price are reasonable for the application at hand. The market supplies whatever quality and price people will accept.
 
Looks like there is a lot of different opinions; buy a more expensive one, return mine for better quality or just make the adjustment because none of them are that accurate. I think I'll return mine bought on amazon and try one directly from a wine supply.

One other question while I have everyone's attention. I usually drop my hydrometer into my 6 gallon pail rather then use the beaker it comes with. Will that distort the reading?
 
No that wont distort the reading. One of the issues I see all of the time is the hydrometer touching the side of the test cylinder, so you have to keep lifting and re-centering while taking a reading to ensure it's not hung up on the wall. In a pail you don't have that issue. I test in the pail routinely during fermentation, it could be a problem if you break the hydrometer in the pail, but it is a risk I accept while others might not.
 
I am going to try LD Carlson this time for the hydrometer. Any reviews on them?
 
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cmason - just wondering how you can be certain the yeast is done and there is no remaining sugar without an accurate read.
 

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