[uisgue]

Hi Doug!  You can do it all at once.  A pack or vial might not have enough yeast for 5 gal., but it's got plenty for 4 L.

Thanks Denny, I think I'll need to do a starter step-up anyway. I'm planning a 10 gallon 1.090 OG Baltic Porter.  Probably will need 2 4-L starters. Maybe it'll be ready for the Christmas party.

[sharg54]

The easy way I found to make a starter for something like a Baltic porter is to make a standard porter like an American or English type first. After that you have plenty of yeast cake and don't need a starter. Just put the Baltic into the same fermenter and let it rock. Now you have two beers a nice porter and a Baltic and no guess work over how much starter you need. You should have no problem going up on OG from a standard Porter to a high gravity porter like a Baltic and it will be ready for Christmas...