I have purchased a Big Berkey recently and ended up with several defective filters, just as was recently mentioned in SurvivalBlog. I discovered this when the unfiltered chlorinated water destroyed a gallon of my sweet tea. The glue that was on it looked a lot like a kind of hot glue! I didn’t want to hassle with the long waiting list, so I removed the excess glue and “re-glued” it with a tube of clear silicone [RTV] caulk that I bought at Home Depot for $4. It is a simple fix and it lasts. Just make sure you follow the instructions on the tube and don’t let the silicon run into the little plastic nozzle. The original glue lasted a week, and the caulk has thusfar lasted 5 months.
Good luck! Enjoy you clean water!! – Thomas D.