Specific Gravity rising

[DixeySJ]

Santa gave me a Tilt Hydrometer and with my current brew (a dark mild) I have been able to monitor the SG and temperature remotely. For the first week, I was pleased to see the SG falling steadily towards the estimated target, but in the last few days it has started to go up again!

OG was 1.036 and the target is 1.008 - the SG reading reached 1.009 but then 1.010 and now 1.011 .. of course, this may always happen, it's just that I wasn't there to see it. Does anyone have any thoughts on this? I gave the fermenter a bit of a 'swirl' and will see how that goes over the next 24 hours. I am wary of stopping fermentation too soon, I generally like to do at least 10 days more usually 2 weeks ... I just can't think of anything that would happen in the fermentation process that would increase specific gravity ... ideas welcome!

 

[cossie.j]

I actually had the same issue with my current brew. Also the temperature was sporadic too? It’s possible that there’s an issue with the app, and it might need an update? However i wouldn’t worry about it too much and it’s always good practice to leave it in the fermenter for at least 2 weeks, to let the yeast clean up after itself

 

[DixeySJ]

I actually had the same issue with my current brew. Also the temperature was sporadic too? It’s possible that there’s an issue with the app, and it might need an update? However i wouldn’t worry about it too much and it’s always good practice to leave it in the fermenter for at least 2 weeks, to let the yeast clean up after itself

Thanks for that - I will keep the faith! Temperature control is rock steady - I am dialling it up towards 20C, I like to start around 18 for the first phase ...

 

[Richie_asg1]

Bubbles forming on the tube giving it more boyancy?

Could be a whole new phenomenon you have discovered.

 

[terrym]

Santa gave me a Tilt Hydrometer and with my current brew (a dark mild) I have been able to monitor the SG and temperature remotely. For the first week, I was pleased to see the SG falling steadily towards the estimated target, but in the last few days it has started to go up again!

OG was 1.036 and the target is 1.008 - the SG reading reached 1.009 but then 1.010 and now 1.011 .. of course, this may always happen, it's just that I wasn't there to see it. Does anyone have any thoughts on this? I gave the fermenter a bit of a 'swirl' and will see how that goes over the next 24 hours. I am wary of stopping fermentation too soon, I generally like to do at least 10 days more usually 2 weeks ... I just can't think of anything that would happen in the fermentation process that would increase specific gravity ... ideas welcome!

Do you have a conventional hydrometer and if so what does it read?
In my experience the only time the SG rises is when you lower the temperature of the beer and then it's usually only a point, rarely two.
And how would you stop the fermentation?? Most beer brewers allow the yeast to do that.

 

[aamcle]

Probably a crust of yeast getting in the way and stopping it reading properly.


Aamcle

 

[DixeySJ]

Thanks for the responses. I have given the fermenter another agitation and also used a sanitised spatula to give the Tilt a spin. The readings oscillated between 1.011 and 1.012, and now seem steady at the latter figure. I would usually take a hydrometer sample off at 10 days, which is tomorrow, so may do that anyway with a view to a recheck after a couple more days. If readings remain steady, I will probably rack off into the conditioning barrel at the two week mark as usual.

I'm wondering if this is a natural phenomenon as fermentation goes from the primary to secondary stage, but I haven't been able to find any articles that describe what I have noticed. It will be interesting to see if the same happens with the next brew ...

 

[AXW123]

I have just started using my tilt hydrometer and noticed that it has gone up a couple of times. On one occasion it had yeast scum on it on the other there seemed to be no particular reason for it. But it was after I have put the dry hops in so I wonder whether or not it was touching the dry hop bag. I do also find that if you turn the phone on and off as I did then it seems to take a little while to calibrate within one point. I have now set up an old phone on constant next to the beer so I don’t need to do that - so it will be interesting to see if there is a difference in how it turns out.

 

[kelper]

I've done over a dozen brews with my Tilt. After the initial stage with lots of krausen I normally clean the Tilt as it gets encrusted. But whatever SG it reads what tells you the most is when it stops dropping. Many times it takes a couple of days to drop one point! So I leave it. Two weeks is the minimum time I've given a fermentation.

 

[DixeySJ]

Thanks for more feedback. @AXW123 I have also rigged up an old iPhone for constant remote monitoring - thereby of course giving me all this data to think about! Thanks @kelper for the tips on cleaning and I agree about the 2 weeks. The only time I have had off flavours was associated with a shorter fermentation time (although there were probably other factors at play) ...

 

[DixeySJ]

UPDATE. Steady state appeared to be reached at 1.012. A leak around the FV tap dictated a move to conditioning at day 12, but it wasn’t likely to change from then. I checked FG with my manual hydrometer and it was the same. Tasting the sample was hopeful, I’ll be drinking some of it a bit young next weekend (party time). Attached pic is a graph of gravity and temp. Interesting to see how the temperature oscillates in the early stages which is presumably due to heat produced by fermentation being corrected by the fridge (May have to zoom in to see that!).

 

[obscure]

I have just started using my tilt hydrometer and noticed that it has gone up a couple of times. On one occasion it had yeast scum on it on the other there seemed to be no particular reason for it. But it was after I have put the dry hops in so I wonder whether or not it was touching the dry hop bag. I do also find that if you turn the phone on and off as I did then it seems to take a little while to calibrate within one point. I have now set up an old phone on constant next to the beer so I don’t need to do that - so it will be interesting to see if there is a difference in how it turns out.

I just bottled a batch yesterday which my tilt was putting at 1.01 was a few days after dry hoping. Took it out with a sterilised spatula cleaned it and it went back to 1.008 (about what I got with a normal hydrometer). As much as I like my tilt it does seem t9 be a persistent problem of it giving weird readings if it gets too much gunk on it.

 

[kelper]

Even if the Tilt gets stuff stuck to it, it will still show you whether or not the SG is still dropping. You should always check the FG with a glass hydrometer so I don't see the problem.

 

[DixeySJ]

Thank you both @kelper and @obscure. Cleaning the tilt at critical time points seems good advice, I’ll be watching my next brew with interest.

 

[AXW123]

Despite the wierd readings - knowing the temperature and specific graft gravity at all times without messing about with the beer is still great information and I feel that I have a much better handle on what’s going on. It has made me much more aware of exact temperature- before it was a vague notion from the tape on the side of my fermenter - now I know exactly and am following recipes much more precisely hopefully with better results.

 

[DixeySJ]

Enjoying some of it tonight. Has turned out fine, just about what I was aiming at.

 

[Twopan]

Interesting thread. I have an iSpindel which I have calibrated twice and it now seems pretty accurate using an offset of +.001. I always use a conventional hydrometer to check the OG and it is consistent with the iSpindel. But then after about 2 hours the iSpindel shows a higher reading. In the current brew it has risen from 1.041 to 1.044 over 7 hours before starting it's descent. Is this a kreusen problem (the temperature is consistent) and do I stick with the first reading for ABV calculation?