Overshooting FG

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Oct 13, 2020
Messages
1,326
Reaction score
771
Seem to be routinely overshooting final gravity. All seems well going into the fermenter - OG there or there about, pitch yeast which seems to kick off in good time and happily do its stuff, but then overshoot FG and often get close to or hit 1.000. Using an iSpindel and hydrometer to check FG. This is obviously because the yeast is chomping its way though all the sugar but does this mean I'm not getting the right balance of Alpha and Beta analyse sugars because I'm not hitting the correct mash temp? I do struggle to regulate mash temps...I'm using a brewzilla and the built in thermometer will be reading one reading, but will measure the temperature of thew wort as it is recirculates which is always a few degrees cooler, but struggle to find thermometers that agree so have no idea where I am on temperature. The Brewzilla thermometer is at the bottom so I'm bound to have a temp gradient from the top of the malt pipe to the bottom so hard to pitch the right temp.

The beer always tastes great but would like to drink a few without getting too hammered!! Any ideas? thanks.
 
Have you checked what your hydrometer reads in water? It would be strange if you were consistently hitting 1.000. What was the OG and the yeast used?
 
the last brew was a NEIPA using S-05 I think and that overshot by about 8 points so got down to about 1.006 against a target of 1.014. The two brews before that was a TT clone using Nottingham Ale yeast which got down to pretty close to 1.000. I know that Nottingham Ale yeast has a reputation of being a bit 'frisky' but even so my thinking is that if I have the right balance of sugars the yeast will feed on the fermentable sugars leaving the non fermentable. The current American Pale ale in the fermentor right now fermented with S-04 and was supposed to finish with a FG of 1.012 but the iSpindel is saying 1.000. Need to corroborate with the hydrometer yet but I can't see there being a 12 point disagree - a couple of points at the most.

Assuming the FG readings are there or there about to within a few points, I'm just wondering what I need to correct to address and get closer to target. Its a grandfather fermenter so fermentation temp control pretty good but wondering if I have enough control over the brewzilla mash temps.
 
Seem to be routinely overshooting final gravity. All seems well going into the fermenter - OG there or there about, pitch yeast which seems to kick off in good time and happily do its stuff, but then overshoot FG and often get close to or hit 1.000. Using an iSpindel and hydrometer to check FG. This is obviously because the yeast is chomping its way though all the sugar but does this mean I'm not getting the right balance of Alpha and Beta analyse sugars because I'm not hitting the correct mash temp? I do struggle to regulate mash temps...I'm using a brewzilla and the built in thermometer will be reading one reading, but will measure the temperature of thew wort as it is recirculates which is always a few degrees cooler, but struggle to find thermometers that agree so have no idea where I am on temperature. The Brewzilla thermometer is at the bottom so I'm bound to have a temp gradient from the top of the malt pipe to the bottom so hard to pitch the right temp.

The beer always tastes great but would like to drink a few without getting too hammered!! Any ideas? thanks.
I don't have a very sophisticated brew kit, but I had a similar problem a few years ago and discovered my mash thermometer was reading about 5°C too high. Since then, I compare my thermometers once a year to see if any are giving bad readings.
 
I think your hydrometer and ispindel calibration would be the first thing I would check as I agree that routinely finishing close to 1.000 would be strange. I also think you would notice it as they would be dry as a bone!

Despite going through the calbration process meticulously, my ispindels are not that accurate and both underreport gravity by about 10 points.
 
It's most unlikely your beer FG is really going down to 10.00 unless you're using loads of sugar in it. There must be something wrong with your instruments. Does the OG come out at what you expect?
 
Although I agree with others that it seems like your instruments are out, I also thought I’d mention that both US-05 and Nottingham often attenuate better than what attenuation calculators and brewing software have set for them by default. I’m using Brewfather and for my latest brew with Nottingham, for example, the default attenuation was 73.7%, but my final figure was 81% (which was 4 gravity points difference). Not enough in its own to account for what you’re experiencing, but might be contributory.
 
I would certainly trial your hydrometer in water as your first check. As said above, if it was finishing at 1.000 it would be very dry and you would likely notice it. Us-05 often gets to about 1.006 for me when mashing at 66c. I would imagine that you would struggle to get it much below that using just malt even if mashing considerably lower by mistake.
 
Also the ispindel could be out significantly if it has some krausen resting on it somewhere. I appreciate it can be calibrated to account for this but there could be a number of variables causing it to read incorrectly.
 

Latest posts

Back
Top