[quote=“560sdl”]The problem is that the buckets don’t really have any sort of gasket to create a real seal. It is just plastic touching plastic. When I sanitize my lids, I shove them down into my fermenting bucket of starsan and it deforms the bucket for a short while. At some point the lid begins to sit less flat or whatever. My guess is that they never made anything resembling a perfect seal. Just enough that more of the Co2 when through the airlock that the top of the bucket.
As long as you have fermentation going on, the seal does not matter, other than piece of mind of watching the bubbles, which is entertaining, I admit.[/quote]
I can’t remeber where I got mine (a competing website I think) but it has a “true brew” logo on it with a beer and wine symbol. It’s 7 gallons to the brim and has a press on type lid with a rubber gasket that fits tight for a great seal. It also has a rubber gasket in a hole in the lid the perfect size for an airlock. It sounds to me like you are using a bottling bucket rather than a pail designed to be a fermenter. It obviously works but is less than ideal especially if you are going to do a single stage ferment.
I’d never try to jam the lid down in the bucket to sanitize it; you deform the lid and bucket, plus scratch it up leaving places for bacteria to hide…