Airlock Back Pressure

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Well-Known Member
Aug 21, 2007
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Minneapolis, MN
I looked for posts about this, but didn't find anything... Basically I added fruit to a mead and it started to ferment. This morning I looked at the 3 piece airlocks and found that the vodka was below the air outlets.

Basically there seems to be back pressure in the carboy that's sucking in the vodka in the airlock.

Does anyone know what causes this and what can be done about it?

anderj said:
Has the wort cooled since it has been capped?

Complete edit: YES and I uncapped it an it continues to suck in after the airlock is replaced. So far my short term solution has been to take the airlock off put a Co2 hose on the plug and pressurize the carboy a little bit. Which doesn't help for very long.
Think I might have an idea...

Blueberries and raspberries have potassium sorbate in them? I put a heater by the carboys to raise the temp to 72F and pitched a half packet of D47 in each of them.

At least at a higher temp I don't have negative airlock pressure, who knows if it'll ferment.