I shattered a 15 gallon glass demijohn recently and vowed never to go back to glass. no injuries but most importantly, i didn't have a way to ferment 10 gallon batches without splitting up. So i decided to try a method that the local homebrew shop / brew on premises uses for all their customers. It involves a 15 gallon drum, like the ones they get malt extract in and a food grade nitrogen purged plastic bag. Just cut a hole through the the cap thingie big enough to fit a 6.5 carboy stopper, slip the bag in the bucket, filler up, aerate and whatnot and then pop in your air lock over the bag. If this works out ok, the next time i might drill a larger hole to fit a bigger stopper this way the bag is so bunched up where the air lock fits.
I do not know right now where to get the bags from, just that i got em from the homebrew shop
Pros: 1) No cleaning or sanitizing this style fermenter EVER as the bags are one use only and come purged and sterile. 3) the empty extract drum was free, and the bags are like 2 dollars, so total money in = cost of airlock and plastic bag.
Cons: The guy at the shop said sometimes the bag ruptures and your probably screwed if that happens


