OG way off 🤷‍♂️

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It was regarding the the volume marks on your AIO and how accurate they are as they can be out by a few litres which will make your amount expected to be wrong.
In other words check the measure marks with water so you know wher you are exactly with your volumes
Just weighed out 10l of water and it was bang. The spacing between the rest of the markings are even so I'm hoping the rest of the markings are also spot on, they're at least consistent 😂
 
@RavenKing
My question about volumes is related to the expansions that occur with temperature.
There's an expansion of the water from 20 c to 100 c.

So 20 litres at 20 celsius has a volume of 21.1 litres at 100 celsius.

So this will influence your calculations as well.
 
@RavenKing
My question about volumes is related to the expansions that occur with temperature.
There's an expansion of the water from 20 c to 100 c.

So 20 litres at 20 celsius has a volume of 21.1 litres at 100 celsius.

So this will influence your calculations as well.
Ah! I didn't really know that, though it seems obvious. I suppose I just assume whatever brewfather spits out is good enough.
 
Hey, thought I'd give an update on this. Did another brew yesterday and after changing a few settings in brewfather I was still didn't hit the expected pre-boil and OG.

Pre-boil should have been 1.054 but was 1.044
OG should have been 1.065 but even after adding a my Belgian Candi syrup and some extra sucrose it still only came to 1.060.

My volumes were spot on though. Pre-boil 26.5l was fine and post-boil of 25l was fine.

So I can only assume my efficiency is wrong?
I did some more playing around in brewfather and found if I set my brewhouse efficiency to 63% it matches the numbers perfectly.
Could there be something wrong my process? That seems low 😬
 
It could be one of those process things that will improve with just experience and seeming to do nothing different, it may also be bad/old malt?
 
It could be one of those process things that will improve with just experience and seeming to do nothing different, it may also be bad/old malt?
Other than my equipment changing recently I don't really do anything differently so maybe I need to get back to basics on the process side.

The malt was delivered from the malt miller only 2 days prior so I suppose there is a chance it was bad/old but not so sure about that tbh.

I'll get there 😁
 
Other than my equipment changing recently I don't really do anything differently so maybe I need to get back to basics on the process side.

The malt was delivered from the malt miller only 2 days prior so I suppose there is a chance it was bad/old but not so sure about that tbh.

I'll get there 😁
I am sure you will going back to basics for a brew or two may just trigger something, the malt sounds ok was just a possible though athumb..
 
Most are not correct some are near some are further away as they are mass produced units.
I know where I am with mine jug filled it carefully , you can also weigh the water which should technically be more accurate
and check the markings on your jug by weighing water in! Seems obvious now, but my jug of choice was 5% out!

Weighing water out is a ballache there is no denying, but once you have absolute confidence in the markings (or you add new markings if the existing ones are wrong) you shouldn't need to do it again.

Brewfather should account for hot expansion automatically (i think, dont think there is a setting to change this although I might be wrong) so once you know your markings are right it should be as simple as just reading it off and plugging it into brewfather.

Also make sure your pump is vented when doing the volume check and this is accounted for is any dead space figures in brewfather. this might be negligible in the grand scheme of things, but as your going to the effort of weighing water you might as well make sure the pump is vented.

I am on brew 8/9 now on new kit and still dialling in. I find it helpful to tweak your equipment profile by calculating averages over a sample of say 5 brew days, for example, grain absorption / boil off etc. Knowing that each brew day your using in your sample, went relatively to plan (remove any outliers / balls ups).

I used this way to dial in my brew in a bag system before my all in one and got the equipment profile pretty well correct and predictable given the higher error margin when squeezing muslin bags and trying to "sparge" / rinse it.
 
Pre-boil should have been 1.054 but was 1.044
OG should have been 1.065 but even after adding a my Belgian Candi syrup and some extra sucrose it still only came to 1.060.
Do you know whether the pre-boil wort was REALLY well stirred? Is there a chance that the low gravity reading was off (in a similar manner to before) because it was taken from the lower gravity final runnings? (Just trying to eliminate variables here)

Was the 1.060 post-boil (when it will have been fully homogenised) and cooled to 20°C? (Again. Trying to eliminate variables).

If it is actually your mash efficiency being low, it could be caused by many things. Not trying to teach you to suck eggs, but how thick/thin was your mash? What temperature and for how long? How cloudy/clear was the wort that came out of your mash? Do you modify the mash pH in any way?

(Most of those have a small effect, but it might point is towards something)
 
My brewhouse efficiency used to be poor with my Robobrew 35 when I first started, around 60 percent.
Later found out about mash efficiency and that was my main area of loss.
No pH control, too large a crush, no salt adjustment, average / inconsistent temperature control, no stirring, too thick a mash, no squeeze of the grains and a lack of patience ( ie mashed a bit longer, slower sparging) all needed optimising to get things better.

Added to this I was taking very few measurements and they weren't the best.

Optimising crush ( finer ) around 3.5 litres per kg of grain and squeezing the grains before sparging made the biggest difference.

Squeezing the grain in the malt pipe extracted the higher concentration sugars and compacted the grain bed which otherwise was so porous that the sparge just ran out as quickly as it went in and there was no time for diffusion out of the grains into the sparge. I suspect if I'd been able to do it a batch sparge would have worked very well.

The other tweaks of all added to the efficiency.

What AIO are you using?
 
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Hey, thought I'd give an update on this. Did another brew yesterday and after changing a few settings in brewfather I was still didn't hit the expected pre-boil and OG.

Pre-boil should have been 1.054 but was 1.044
OG should have been 1.065 but even after adding a my Belgian Candi syrup and some extra sucrose it still only came to 1.060.

My volumes were spot on though. Pre-boil 26.5l was fine and post-boil of 25l was fine.

So I can only assume my efficiency is wrong?
I did some more playing around in brewfather and found if I set my brewhouse efficiency to 63% it matches the numbers perfectly.
Could there be something wrong my process? That seems low 😬
I don't use expensive kit, simply a BIAB grain bag, a 23L kettle and a dunk sparge vessel (the bin that will be later used as the FV). However, I am struggling to get my efficiency above 57%. I recognise that BIAB is less efficient, and I have started using a 10 minute dunk sparge at 77°. This has got it from 55% to 57%, but I still dream of 63%!
 
I don't use expensive kit, simply a BIAB grain bag, a 23L kettle and a dunk sparge vessel (the bin that will be later used as the FV). However, I am struggling to get my efficiency above 57%. I recognise that BIAB is less efficient, and I have started using a 10 minute dunk sparge at 77°. This has got it from 55% to 57%, but I still dream of 63%!
How much do you stir you mash? Do you stir when you dunk sparge? I don't do BIAB, but I think that might increase your efficiency.
 
How much do you stir you mash? Do you stir when you dunk sparge? I don't do BIAB, but I think that might increase your efficiency.
Thanks. I do stir the mash in the bag, but could probably do this more often. I haven't stirred the grain in the sparge before, just lowered the bag into about 8L of hot water at 77° and left it for 10 minutes. I will start adding a stir to the sparge. I also drain the bag well after both mash and sparge through a large stainless steel colander bought for the purpose. Thanks for the tip.
 
There comes a point where more stirring won't help the mash (and if you're already stirring plenty at the start) then you've probably already hit that point.

Stiring during your sparge will make cloudier wort but probably help efficiency to some degree, so worth a try and see how it affects your brew.

Squeezing the bag also apparently helps a lot

But I've never done BIAB so I'm just repeating what I've heard.
 
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Hurrah! I felt I should post my solution to low efficiency using BIAB method. I have just hit 75%. The steps were: mash longer (90 minutes) at a lower temperature (62°). Prod the mash at the start to ensure grain gets fully soaked and then stir gently for a couple of minutes. Stir again after a few minutes as the grain loosens. Mash for 90 minutes. Using a second kettle, heat 9 litres of water to 75°. Dunk sparge the bag in the sparge water. Stir again and leave for 10 to 20 minutes. Lift bag and transfer to large colander on top of first kettle. Leave the bag to drain into the kettle under its own weight. Add sparge water to first kettle and check pre-boil gravity, remembering to adjust for temperature. Top up as necessary to pre-boil volume. Use tried this and achieved 75% efficiency.
 
I don't use expensive kit, simply a BIAB grain bag, a 23L kettle and a dunk sparge vessel (the bin that will be later used as the FV). However, I am struggling to get my efficiency above 57%. I recognise that BIAB is less efficient, and I have started using a 10 minute dunk sparge at 77°. This has got it from 55% to 57%, but I still dream of 63%!
55% - luxury! I used to dream of 55% we couldn't afford water , had to lick the grain with our tongues 30 hours a day till our mouth was dry!
 

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