I only have a 5 gallon (and about an extra quart at the top) carboy. Here's my issue before I give my question. When I have only 4 gallons of wort and pitch the yeast, the fermentation get so active that it ALMOST comes out of the carboy. My question is, can I simply add a gallon of distilled water to the fermented beer in the racking bucket when I'm adding the priming sugar? Bare in mind that the recipe is 6 lbs of dme and 3 pounds of grain (partial mash) (BIAB). So there shouldn't be an issue with it diluting out. I just have a feeling that the yeast may not be able to do its thing properly with such concentrated wort.