I’ve had a stuck mash on my gravity fed set up. Unfortunately it’s happened twice and both times were for different reasons. In either case I successfully saved both batches of beer.
If you encounter this again the quick fix would be to what others have posted. Blow air back in to try and open...
I always transferred my beer to a secondary during the first 2-3 years when I got started. I haven’t used anything but a primary for the last 5-6 years and haven’t noticed a significant difference aside from saving time and sanitizing solution. Either way to get to your question just keep it...
Just for my own knowledge and curiosity, I thought that oxidation wasn’t a big concern pre-fermentation? It’s recommended to aerate the wort prior to pitching the yeast. So how can the wort become oxidized at this stage? Or am I not understanding?