No bubbles when fermenting.

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Mickyd

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I’m baffled
Just finished an AG NEIPA. OG 1.055 pitched 2 packets of safale 05 at 18degrees. I ferment in a SS vessel with a blow off tube into jar of starsan, so cannot see the wort and rely on CO2 blowoff to detect activity. After 3 days no bubbles. I raised temperature and gave it a bit of a shake. Next day still nothing but I took a gravity reading - 1.035. So it was fermenting but no CO2.
How it it so? I pressure tested the vessel and no other leaks where CO2 can escape.
Cheers, Mike
 

Ronwales

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I’m baffled
Just finished an AG NEIPA. OG 1.055 pitched 2 packets of safale 05 at 18degrees. I ferment in a SS vessel with a blow off tube into jar of starsan, so cannot see the wort and rely on CO2 blowoff to detect activity. After 3 days no bubbles. I raised temperature and gave it a bit of a shake. Next day still nothing but I took a gravity reading - 1.035. So it was fermenting but no CO2.
How it it so? I pressure tested the vessel and no other leaks where CO2 can escape.
Cheers, Mike
Yeah its a pretty common in the plastic fermenter
 

Ronwales

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I'd say its fermenting just leave and definitely don't shake as you might oxidise your beer.
 

kadmium

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There is a leak somewhere. Has to be, because if its fermenting its making pressure and if its gravity is dropping then its fermenting.

Doesn't take much for a smallllllll leak. You can mix up some starsan in a spray bottle and spray around seals etc to see if it foams up.
 

Mickyd

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There is a leak somewhere. Has to be, because if its fermenting its making pressure and if its gravity is dropping then its fermenting.

Doesn't take much for a smallllllll leak. You can mix up some starsan in a spray bottle and spray around seals etc to see if it foams up.
I have pressure tested the vessel and it’s tight.
 

MHB

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No, you have just pressure tested and not found the leak, because
There is a leak somewhere. Has to be, because if its fermenting its making pressure and if its gravity is dropping then its fermenting.

Doesn't take much for a smallllllll leak. You can mix up some starsan in a spray bottle and spray around seals etc to see if it foams up.
He's right, personally I use a blend of dishwashing liquid and glycerin to find leaks but same answer, if the SG is dropping its fermenting, if its fermenting its making CO2...
Mark
 

kadmium

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He's right
If only I could get my wife to admit that once in a while!!

Pressure testing won't necessarily find the leak. The same reason you don't always find leaks in kegs above serving pressure, as the increased pressure can seal shut the vessel.

The vessel at low pressure can leak. How did you pressure test it if you're using a blow off?
 

Mickyd

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If only I could get my wife to admit that once in a while!!

Pressure testing won't necessarily find the leak. The same reason you don't always find leaks in kegs above serving pressure, as the increased pressure can seal shut the vessel.

The vessel at low pressure can leak. How did you pressure test it if you're using a blow off?
The blow off has a valve. Even if there is a small leak, with the blowoff open, most of the CO2 will exit through the blowoff. Hence my bafflement.
 

kadmium

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My guess is the leak is not present under pressure but under atmospheric conditions it's present. Its a simple fact that yeast consume sugar and produce co2 (and 500 other chemicals)

Therefore if the gravity is dropping co2 is being produced. Airlock activity is not an accurate way to check fermentation.

What is the fermenter?
 

Mickyd

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I have a gas connector on the lid so I can closed loop keg transfer. I close the blow off and pump some CO2 in. Leave it and see if it maintained pressure. A bit agricultural and may not detect a small leak. I’ll try the detergent test.
 

kadmium

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Yep fair enough, and like I said earlier it can be that under pressure no leak but under no pressure leaks. Pretty common
 
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Same SS fermenter setup with blow off tube. Same problem: no bubbles but SG dropping. Figured out afterwards the lid may not have been on snugly all the way around. Took care to seat the lid/silicone gasket properly all the way around. Problem did not recur. Conclusion, no structural leaks.
 

Mickyd

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Thanks for your help guys.
I really just wanted to make sure there wasn’t something else I was missing eg. contamination causing some weird reactions.

I changed from using gladwrap, to the lid with blowoff, about the same time that I changed from hydrating dry yeast to pitching dry. I thought it may have had something to do with the dry pitching.

I’ll do some more checking and tighten things up and see how it goes.
 

MHB

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The Olive Oli drums I have seen tend to have a fairly thin silicone O-Ring, without any lube on the O-Ring it can catch and pucker as the lid is tightened. The lid is moving both across (or around) and down at the same time.
I suspect when used for Olive oil the question of a bit of lube is moot, but it sure helps when brewing.
Mark
 

Mickyd

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Good point Mark. It does have said O ring. What could I use as lube without risking contamination?
 

kadmium

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Lubrifilm which you should have if you keg, but it's cheap, safe and effective. It's made in the USA a small tube will last ages.
 

MHB

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Lots of options, I mostly use Rocol Food Grade Silicone Grease, Inox make a good one, all the major brewing equipment have one on offer...
Vaseline isn't a good choice, but any of the food grade lubricants on the market are a must have if you are a kegger.
I'm into the second half of my tube of Rocol but its over 10 years old and been used at home and work, so yes you won be spending lots on lube.
Mark
 

GrumpyPaul

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You're more likely to have to buy a new tube because you lose the tube somewhere in the brew shed than because it runs out.

You will also buy more brew stuff when you do replace it because shipping is more than the cost of lube and it just doesnt seem right to pay shipping just for a tube of lube.

I heard of a guy that did this..just sayin'
 

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