Q's about top-cropping yeast

I just made my first batch of a Belgian Wit. I used Wyeast 3944, termed a "true" top cropping yeast. I see why. Man, that stuff really puts up the krauzen!
I have a few questions-
first, I have always figured the end of primary fermentation by the yeast cake dropping to the bottom of the fermenter, and the cessation- or near cessation- of CO2 production. It appears this yeast may not fall to the bottom as some do- is that correct? How about CO2 production? My very elementary understanding of the fermentation cycle is that the CO2 (and alcohol) are the by-products of yeast's fermentation of the sugars in the wort. Seems like the CO2 would stop when fermentation ends.
Next, I have read in some places where it is better to stir the fermenter to "rouse" the yeast back into the wort. It is claimed they will all go to the top and be out of the wort, thus not doing their work. Do any of you have experience with that process?
I originally propagated up .8 liter of 3944 for 24 hours. It was very active and showed a lot of cell growth. Krausen started in 8 hours, it blew off in 24 hours and has been caked to the top of a 6 gallon ever since. That beer will either be the driest I've ever made or that's the laziest yeast I ever saw!
Comments?

What temperature fermentation? OG and FG now?

belgian yeast usually sticks around a lot longer than other yeasts, IME.

But other than that advice, hydrometer hydrometer hydrometer.

WBC said:

What temperature fermentation? OG and FG now?

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It started at 68F and 1.060, still 68F, just weighed it at 1.024, so it appears that even tho it's been at krausen for a week, it still needs some time. It is still obviously fermenting, and I think I will continue to "rouse" it once a day, as that seems to make it quite a bit more active. I think this is a lazy yeast I have never experienced before.....

This is a good lesson in the need of yeast starters. Did you pitch rehydrated yeast into 75F to 80F wort? This is the best way to get fermentation going right away. If using dry yeasts then rehydrate in boiled/cooled to 85F water for best results. Do not stir for 15 minutes and only then swirl it when the time is up and then wait 5 more minutes and pitch into the 80 degree wort. Lower to 65 F only after you see the krausen starting.

I used a vial of WLP 400 and it took 3 weeks. So...definitely make a starter or pitch onto a cake if you want fast. I made a second batch just to take advantage of the cake.

WBC said:

This is a good lesson in the need of yeast starters.

Click to expand...

I respect your experience, but I did pitch a big starter. I took a 3944 Propagator, used a stir plate to propagate up .8 liter of yeast starter. It was very active. I used yeast nutrient in the starter, and with all the vortex of the stir plate, should have had about 250 billion cells in 24 hours. This by calculation should be an adequate pitch for a 1.060 beer. It was proven by the start- 8 hrs to cake- and by krauzen- 24 hours. It has gone full krausen to blow-off 4 times now, but still is at 1.024 with a lot of fermentation activity.
I'm forced to conclude the 3944 just takes a long time to process all the sugars in the wort.
There is some anecdotal evidence of that in this thread.
I hoped some others may have experience with this strain that they could relate.
Thanks all for your input!

The fact that it is still going good is a sign that the yeast were having trouble eating all that sugar. I have had that happen to a lesser degree but I can understand your concern and did not want to throw rocks but maybe the starter needed to increase in numbers for some reason and that is why it is taking longer. That is a strong beer.