Originally Posted by fritz_monroe
How about the oxygenation comment? How do you folks handle aeration? Is the air pump with an air stone adequate?
It really depends on what kind of yeast you like to use and whether or not you brew a lot of big beers (OGs of 1.060+)
Big beers + liquid yeast using a "splashing" type of aeration is going to be a really puny ferment. You really need an O2 system.
On the opposite end, dry yeast or starter pitching + small beers will ferment with a really small amount of dissolved O2 which you can get by splashing and shaking.
You'll get a lot o people claiming things work out fine using all kinds of methods which puts this into the catagory of anecdotal but here's what most people agree on with yeast and aeration:
1. Bigger beers require higher numbers of healthy viable yeast in order to hit "expected" attenuations.
2. The more viable cells you pitch, the less O2 needs to be dissolved in the wort. This makes sense in that an O2 rich environment encourages reproduction. If you have enough cells to begin with, they only need SOME O2 to store energy for the ferment.
3. Dry yeasts can be pitched into most beers with moderate O2 saturation while liquids (without making a starter) need a bit more O2.
etc. etc. Bottom line, if you like liquid yeast, I'd suggest making starters or injecting pure O2 (or inject pure O2 into your starter).