Should I Just Ignore My Hydrometer Readings?

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mancer62

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I cant get used to my replacement hydrometer which I got a while back. This evening I made a (1.75 kg) malt extract IPA + 1kg Brewing Sugar made to 40 pints. Once mixed and the temp at 25 C I took a reading which was 1032 which to me seems very low. The hydrometer is calibrated to 20 C. This kit advertises an ABV of 5% but with an OG of 1032I would hardly think I will be achieving that.
I then made a Bulldog Rajas Reward IPA Premium Beer Kit (3.4kg) again to 40 pints this time no sugar was required as the kit had everything in it. However again my hydrometer was approx at 1032 at 26 C with the kit advertsing an ABV of 4.8%
Therefore should I just dismiss the hydrometer readings and go along with what it says the ABV will be on the box?
 
I cant get used to my replacement hydrometer which I got a while back. This evening I made a (1.75 kg) malt extract IPA + 1kg Brewing Sugar made to 40 pints. Once mixed and the temp at 25 C I took a reading which was 1032 which to me seems very low. The hydrometer is calibrated to 20 C. This kit advertises an ABV of 5% but with an OG of 1032I would hardly think I will be achieving that.
I then made a Bulldog Rajas Reward IPA Premium Beer Kit (3.4kg) again to 40 pints this time no sugar was required as the kit had everything in it. However again my hydrometer was approx at 1032 at 26 C with the kit advertsing an ABV of 4.8%
Therefore should I just dismiss the hydrometer readings and go along with what it says the ABV will be on the box?
Make up a sugar solution of a known quantity (eg, use a calculator like this one to say how much sugar to dissolve in a given volume of water). Then measure the gravity with your hydrometer and see what it says. Also check the calibration in plain water like @buddsy says.
 
If you're using your hydrometer correctly then no reason to not believe it. I tested my cheap eBay hydrometer in distilled water and it was 4 points out so that is probably the order of magnitude of error from the hydrometer. I tend to use a refractometer during brewing, a floating hydrometer to monitor fermentation progress and not actual readings, and a traditional floating hydrometer for the official FG - though my floating hydrometer (is-spindel) is hugely out at the start of fermentation but usually ends up agreeing with the traditional hydrometer for FG readings.
 
though my floating hydrometer (is-spindel) is hugely out at the start
Have you calibrated it? Mine was hugely out on OG too until I calibrated it. Now it's within one or two points of my hydrometer reading every time
 
Have you calibrated it? Mine was hugely out on OG too until I calibrated it. Now it's within one or two points of my hydrometer reading every time
Can you calibrate them yourself? Is it a case of gently tapping to move the paper inside? They seem pretty poor design to me.

buddsy
 
Can you calibrate them yourself? Is it a case of gently tapping to move the paper inside? They seem pretty poor design to me.

buddsy
Sorry, I was meaning the iSpindel. As far as I'm aware, you can't calibrate traditional hydrometers
 
I just tested it in 20 C water and it read 0.
However on the many occasions I have made beer I have never got OG readings as low as 1032 after using a tin of extract and a kilo of brewing sugar it just doesn't seem right to me. It has always been in the 1040/1044 region.
Also the 3.4kg Bulldog Raja Reward kit I done is a kit where everything is included and claims an ABV of 4.8%.........I would therefore assume that to achieve this the OG would have to be way higher than 1032.
It is now 14 hours or so since I made these brews and have added the yeast. The fermentation has already started in the Raja with the airlock bubbling nicely.
With the beers now at room temp would it be worthwhile taking another hydrometer reading or would this just give me false readings?
 
I cant get used to my replacement hydrometer which I got a while back. This evening I made a (1.75 kg) malt extract IPA + 1kg Brewing Sugar made to 40 pints. Once mixed and the temp at 25 C I took a reading which was 1032 which to me seems very low. The hydrometer is calibrated to 20 C. This kit advertises an ABV of 5% but with an OG of 1032I would hardly think I will be achieving that.
I then made a Bulldog Rajas Reward IPA Premium Beer Kit (3.4kg) again to 40 pints this time no sugar was required as the kit had everything in it. However again my hydrometer was approx at 1032 at 26 C with the kit advertsing an ABV of 4.8%
Therefore should I just dismiss the hydrometer readings and go along with what it says the ABV will be on the box?
mine is off after checking in 20c water now and again by .002 the one I had before them was off by .003 - just add or subtract the number you get when measuring wort.
 
Have you calibrated it? Mine was hugely out on OG too until I calibrated it. Now it's within one or two points of my hydrometer reading every time
Yep..did the zero point calibration, the weighting calibration and the proper calibration, the full process. Done it across two units now and both have similar characteristics. To be honest I can't be bothered wasting time on them, if they're good enough to track fermentation progress then that is their greatest benefit for me so no big deal for me to take a single hydrometer FG reading once the iSpindel has confirmed the end of fermentation. The whole concept of them is flawed as they are bobbled about during fermentation, measurement compromised by lumps of Krause sticking to them or getting hung up on the side of the fermenter, floating dip tubes, glycol coils ets. as well has having dry hops dumped on them.
 
I measured and marked my FV at exactly 40 pints so I know that's 100% accurate but I think an OG of 1032 would be struggling to give me 4.8% ABV would it not? So do I just trust there's something wrong with the hydrometer reading for whatever reason and just go with the estimated ABV on the box?
 
No one has mentioned the possibility of incomplete mixing of the ingredients yet. That would give you a low OG reading.
That was my first thought as well.

The impression I had was that the OG on these kits was almost guaranteed to match the instructions (subject to the accuracy of the water measurements but that wouldn’t knock it too much) due to the nature of it being a set weight of extract watered down with a set amount of water.
 
Sorry, I was meaning the iSpindel. As far as I'm aware, you can't calibrate traditional hydrometers

You can if they "over read".

All you need to do is to add additional weight to the hydrometer....this is most easily achieved by the use of electrical tape wrapped around the very top of the hydrometer...it shoudnt take much to balance it properly...and is easily fine tunable by cutting the length of tape used.
 
i gave the ingredients a really good long stir so i dont think it will be that. as a matter of interest if it isn't stirred properly at this stage will the ingredients still ferment out fully and give the expected ABV?
 
i gave the ingredients a really good long stir so i dont think it will be that. as a matter of interest if it isn't stirred properly at this stage will the ingredients still ferment out fully and give the expected ABV?
Yes, they will.
 
If you have fully dissolved and mixed the kits then your Hydrometer is out.
For the cost go to Wilko's and buy another for £3/4 quid and take a fresh reading with this.
You always need a spare Hydrometer as they do break at the most unfortunate moments
 
I measured and marked my FV at exactly 40 pints so I know that's 100% accurate but I think an OG of 1032 would be struggling to give me 4.8% ABV would it not? So do I just trust there's something wrong with the hydrometer reading for whatever reason and just go with the estimated ABV on the box?
Test the meter in water at 20c. If it gives you 0 then trust the meter and not the kit. No way of testing if the kit is accurate
 

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