Originally Posted by YooperBrew
An extra package of yeast is fine- it's not going to have any effect. That stuff on the bottom with yeast, and possibly some colored material, is the "lees". Lees will form in secondary, too, but not as much.
FWIW, I use 1/8 tspn yeast to begin a starter to pitch one gallon. I don't always use a starter, but it is the best way to do it. The rest of the dry yeast has to be stored under vacuum and refrigerated or it will die. If you don't have a way to vacuum your yeast, just pitch it all at once.
Using this method I can use one package of yeast to start 15(ish) one gallon batches from one package of yeast.
Otherwise, for a one to five gallon batch, one package is fine; more won't hurt or help. If you plan to ferment more than five gallons with no starter, I would advise you to use more than one package.
I like to begin a starter with the must, but that's just me. You can use sugar-water and a little nutrient and it will work just fine.
You can pitch ten packages to one gallon of must and it won't hurt. It's just wasteful, not harmful. It will turn out the same either way.