Thanks for the reply.
Yes, it's possible to buy Fido jars here, but also there are very similar jars for slightly lesser price in IKEA, just the name is different (KORKEN). Of course I've tried one of these, but not the way they're supposed to be used while fermenting (burping). It was one of my DIY projects, got myself a drill bit for glass and made a hole into the lid, then used a water airlock sealed in the lid with a piece of silicon hose. It didn't work out that well, because I wasn't able to seal the water-lock completely airtight and couldn't use a silicon gromet instead of the little hose, because the glass lid of the jar is too thick. Still, the ferment turned out fine eventually.
There's a standard type of glass here (about 900 ml volume), which is used for beet root pickles, honey, sauerkraut and lot of other food sold in the stores. It has a screwing lid, that is about half height of the lid for the mason jar. It has a similar rubber band on the inner side, so when you screw it, it's pretty much airtight from the outside, yet at the same time it allows the over-pressured gas produced during the fermentation to escape along with the redundant fluid. But obviously this is not a real airtight solution (and a bit messy), the same goes for burping (letting oxygen in). Another (main) thing I don't like this way is the result can become a bit fizzy. So those are the reason I prefer the way of water-lock. In my opinion the overhead space needed is the same with the Fido jars as you don't fill the glass up to the edge and the small area shaped by the lid into which stands out the tube of the water-lock is free anyway. Well, I need a little bit of space for the glass weight stone, but that would be the same situation using Fido, too
.
