Question about Krausen, Air Locks and Stout

Just a quick question that's kind of amateurish, but something I'm still curious about. If nothing else, maybe other readers will benefit. I've got my first stout with specialty grains (barley that I roasted myself), as a full batch, and it's fermenting as we speak. A krausen formed in a little over 3 days of fermentation, but the only thing that's happening in the airlock (it's one of those curved Italian ones for $1) is the fluid from the outlet side is pushing about an inch down but it won't bubble.

Does this mean that the seal isn't very good or is there just not enough force from a vigorous fermentation? I had put in a fair bit of yeast nutrient in there, about a half ounce and made sure the wort was aerated. Beyond that, it seems like a nice, healthy krausen but I'm kind of surprised by the lack of airlock action. I'm not worried that it won't ferment but I'm kind of disappointed that it's not that vigorous after all of the nutrient and so on that it's received.

Is this just a trait of the style or just "how it is"? Thanks, everyone.

Im not too experienced but, my guess is it may have had a fast fermentation.

Sounds like a poor seal to me. If there is good fermentation (nice krausen) then the yeast is putting out the CO2 like it should. It shouldn't be a problem since you've got a bit of overpressure - CO2 being pushed out means air and nasties can't get in.

Thanks for your responses. I sealed the gasket on the fermentor and I've got bubbles. I didn't think it'd be so simple. :cross:

I've had a couple stouts push thru the airlock. yeast in the airlock and on the lid.
Another blew the lid off after filling the airlock with yeast and wort.
Another with krausen 11 inches up the walls of a 14 gallon fermenter.

So yes stouts ferment quite heavily.