Oh sure, blame it on the children.
Did you pitch the same amount of starter in both? Obviously, there's more sugar in the more-full carboy and the yeast to fermentables ratio was different. Maybe there was an underpitch that needed to catch up. I'unno., just a guess.
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Bottling the Belgian: A Photo Odyssey
Beer is the mind-killer. Beer is the little death that brings total obliteration. I will face my beer. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see it's path. When the beer has gone there will be nothing. Only I will remain.