I really need to thank those who answered on last posts. You guys clarified a lot of things for me.
But…
I’m once again asking for your knowledge.
I won’t explain things as I want to make it short, so I will also thank those who answer in advance:
1 - I still can’t understand the difference between primary and secondary fermentation and when do I need or not to do both.
2 - I’ve seen people doing open and closed fermentations. Se said even here that it’s good to have an open since you can just dig solid stuff back to the bottom, and some just close everything and put an airlock.
2.1 - what’s the difference between them? I thought that letting it open would be bad as yeast needs an anaerobic environment.
2.2 - When should I choose one of them or both?
1 the only time secondary is needed is when you add more fermentables, like fruit
2 closed fermentation is much more popular. You can do open fermentation, loosely covered, but you need to close it once krausen falls. But in general, use closed.
Transferring your beer from one fermenter to another is not going to give you a secondary fermentation unless you add more sugar to it. The reason some people transfer is to get the beer off the sediment, either because they think it will make the beer clearer or because they want to reuse the yeast. Transferring to a secondary fermenter will make oxygen pick-up more likely which will lead to off flavors in most styles. So, usually, most brewers don’t transfer until it’s time to package…
Open fermentation is not necessary. It will make it easier for local microflora to float into the fermenting wort, which would be fine if you’re making a lambic, but a closed fermenter with some sort of air lock will keep it fermenting with the yeast you intended to use.
1 i am an outlier, for doing “secondaries”. i do them, because i prefer the clarity i can get by using gelatin in primary ~2 or 3 days before i transfer the beer to a second container (i do not expect, want or get any further fermentation) in the second container. then i bottled about a week after that and i get clearer beer with less sediment. i think most homebrewers here and in general don’t “secondary” anymore. the reason and drawback is oxygen exposure from moving it around. for the beers i do i dont feel like its an issue.
if i have a very flocculant yeast that really clears up the beer in primary i might not do a secondary, it all depends on how i think it looks. for super powdery yeasts and in styles i want it to be clear, i do.
2 if youre just starting i would try to stick with fermentation with the lid/bung+airlock on, though i know some yeasts make very protective heads. but why risk it when youre just getting the basics down?