# Hydrometers accuracy



## TEDOW (Nov 5, 2006)

Greetings: I'm interested in knowing if there are higher quality Hydometers available? I currently own two, one is .003 off and the other .004 off. This is reading it at 60 degrees F. Are they only right at sea level and anyone using them at a higher than sea level altitude needs to compensate in all readings?

Anyone know?

This looks like a great forum and I look forward to learning much from the members.

T


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## Caplan (Nov 5, 2006)

From what I remember of reading about this in the past altitude has no real effect on a hydrometer. Altitude obviously affects air pressure but as water is much denser than air (500 to a 100 times denser IIRC) the 'correction' needed is is something like '1 PPM at a 1 mile high'.

As long as you know the temperature of the wine and have calculated for any anomalies at it's calibrated temperature (as you have) I'd continue as before.

Hydrometers IMHO are only as 'accurate' as the person reading the result anyway. Trying to judge the bottom of the meniscus with red foam in the way is sometimes tricky! 

As far as more 'accuracy' is concerned have you considered a wine refractometer?


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## TEDOW (Nov 5, 2006)

Thanks, I have never considered a refractor, as I thought that was an instrument only used to measure the sugar levels of grapes. I did not know it could be used to measure Specific Gravity of must.

I will look into these.

Thanks

T


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## Luc (Nov 5, 2006)

The SG of water is 1000. So if the temperature drops the SG will vary as well as if the temperature rises. So temperature is an issue to be concerned about. Look at the manual of your Hydrometer at what temperature it is accurate. As a Hobby scubadiver I know that altitude is an issue (so is attitude ) but not for our purposes. The altitude differences are to small to influence the readings of the hydrometer. Also temperature differences are mostly ' over classified' because a temperature difference of 5 degrees celsius will influence the amount of calculated alcohol hardly. I have a table somewhere for those who are interested. Best regards, Luc


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## Bob M (Nov 8, 2006)

Check what the calibration temp for hydrometer is. Some are 15C some 20C and some are 25C. 20C tends to be the most common but 25C ones are often used in tropics. 15C used to be the most common temp for older english hydrometers.
Bob M


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## smurfe (Nov 14, 2006)

I agree, there is really no difference in any hydrometer I have used. I can't help you with the altitude thing as I live at dead sea level. In regards to the refractometer I agree here as well and prefer it over the hydrometer. I use THIS REFRACTOMETER and really like it. There is less mess to clean. Less exposure to your wines by not having to draw out a substantial sample to test. You only draw a few drops into an eye dropper. 

Smurfe


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## coulee29 (Mar 2, 2007)

I ordered a hydrometer that ranges from -5 to 5 brix or SG 0.980 to 1.020. It hasn't been delivered yet, but I assume it will give a more precise reading for that range than a standard hydrometer. I plan on using it for stopping fermentation early and leaving unfermented sugars to sweeten my wine. I am a newbie, but I think it will be useful. Hydrometers with other ranges are also avail. at morewinemaking.com.

Coulee


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## cpfan (Mar 2, 2007)

coulee29 said:


> I ordered a hydrometer that ranges from -5 to 5 brix or SG 0.980 to 1.020. It hasn't been delivered yet, but I assume it will give a more precise reading for that range than a standard hydrometer. I plan on using it for stopping fermentation early and leaving unfermented sugars to sweeten my wine. I am a newbie, but I think it will be useful. Hydrometers with other ranges are also avail. at morewinemaking.com.
> 
> Coulee


Keep us informed. Sounds like it might be a good hydrometer for some of us.

BTW, stopping an active yeast early isn't as easy as it sounds. How do you plan to do it?

Steve


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## coulee29 (Mar 3, 2007)

*Stopping fermentation early?*

I am making a Vitner's Hrvest Gooseberry wine. The OG was higher than I expected (1.102) so I plan on stopping the fermentation early. The book I read recommends this instead of sweetening after stabilization (if the OG is high enough for the proper amnount of alcohol). 

The wine is now in the secondary fermenter. When the SG gets lower, I'll set the carboy in a cool area under 45 F to slow the fermentation and then add sorbate. Can I add fining agents at the same time? At what SG should I stop fermentation?


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