Dear EC Kraus,
I hope you can help me out. I am having a problem with my 5 gallon glass carboy fermenter. I started a wine from raspberries a few days ago in my bucket fermenter. Now its time to put the wine in the carboy but the rubber stopper will not stay in the opening. It keeps coming out/coming loose. I ordered the size your company suggest. Any ideas?
This issue can arise if there is moisture on either the stopper or your 5 gallon glass carboy. Both the side wall of the stopper and the inside of the carboy’s opening is very smooth. This smoothness is what allows the stopper to seal the carboy air-tight, but just a little bit of moisture can cause slippage, allowing the stopper to back out of the opening. This is what you are experiencing.
My suggestion is to get a paper towel and dry the stopper off completely. Then dry the inside of the carboy’s opening. Once you eliminate the moisture in these two areas, you should be able to obtain a permanent, snug fit.
If this does not solve you problem, you can try going to the next size smaller stopper, but this should not be necessary. You can also use a wire to strap down the rubber stopper. Just wrap the wire around the neck of the carboy then across the top of the stopper. Bailing wire seems to work the best for this.
I hope this helps you out.
Customer Service at E. C. Kraus
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.