SG issues

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remnarctrebor

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Hi everyone, long time troll, first time poster!

I'm having issues when brewing with determining SG/FG and percentage. I'm using both a hydrometer and a refractometer but the hydrometer SG reading always seems low but finishes in about that right place and the refractometer SG reading seems about right but then stops high. The refractometer also stops changing before the hydrometer does. Any ideas on a solution?

I'll happily provide any other details that may help or the latest recipe and readings if it might help
 
I'm also having refractometer reading poblems at the mo. I'm putting them down to my use of the instrument rather than anything else until i work out what the problem actually is.

I think you should believe the hydrometer before the refrectometer.
 
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I'm having issues when brewing with determining SG/FG and percentage. I'm using both a hydrometer and a refractometer but the hydrometer SG reading always seems low but finishes in about that right place and the refractometer SG reading seems about right but then stops high. The refractometer also stops changing before the hydrometer does. Any ideas on a solution?
...

How are you converting the refractometer native "Brix" to SG? And does this allow for the beer having been fermenting? I'm guessing this is one of those "dual scale" refractometers which could result in the comments you're making.

As for the hydrometer, no idea! Kept breaking all mine! So, contrary to nbpicklesno2 I'd believe the refractometer first (my hydrometer is in pieces and somewhat unreliable as a result).
 
Thanks for the replies. I'm using Beer Smith to convert Brix to SG do I'm assuming it's pretty accurate, it also has a tool for measuring Brix in fermenting beer. Don't think the refractometer is dual scale but I'll definitely check when I next take a reading
 
Nay... I was guessing that you had one of these refractometers with a dual Brix and SG scale. Tempting, but... They are a bit dodgy, but its obviously not the case that you have one.

In Beersmith I can assume you're using the refractometer tool to convert brix to SG. Just be sure you are using the appropriate calculation selection ("unfermented wort gravity" for an OG and "fermenting wort gravity", the latter requires you enter the OG so it can work out the alcohol it must allow for).
 
Are you kit brewing ?

A low starting gravity but a final gravity which is about right suggests you are not mixing the kit contents well enough with your water when making up in the fv - assuming you are using kits ?

If all grain, not sure but are you taking a SG reading at 20°C or thereabouts ? most hydrometers are calibrated at 21°C I think. If taking your SG at higher temps then it will need to be adjusted for the temperature.

You can also test your hydrometers accuracy in normal water - should read 1.000 at 20-21°C in normal water

Never used a refractometer so can't help wih that.
 
I'm all grain brewing and the readings are being taken at or around 20°C which is what my hydrometer is calibrated to. I'll definitely check it in water, is there any solution if it's not 1.000 or is it time to get a new one?
 
I'm all grain brewing and the readings are being taken at or around 20°C which is what my hydrometer is calibrated to. I'll definitely check it in water, is there any solution if it's not 1.000 or is it time to get a new one?

The paper gauge inside the glass can slip a bit. You can compensate for it if its 'out' when tested in water at 20°C.

For example if it reads 0.994 in water you know its reading 6 points too low.

So from that point when you measure a starting gravity of a brew and it reads , for example, 1.040 then its actually 1.046 (6 points higher).

Or buy a new one and hope its accurate :lol:
 
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