3 week old kreusen?

My belgian triple (og 1.080) is in its third week in the primary. It still has about 1/2 an inch of kreusen hanging out on top of the brew.

The gravity is currently 1.030, and it still has a bit of a sulfer smell to it. No airlock activity. I'm using Wyeast trappist ale yeast.

Is 3 weeks a long time for there to still be kreusen? I'm fermenting at the lower end of the yeast: 65 degrees air temperature around the fermenter. Should I ease the temp up to the 70s?

When I used the Wyeast Belgian Witbier yeast it took 30 days to go from 1.046 to 1.010 and the temp was an irresponsible 26*C (79*F). It had a Krausen up until the last couple of days. Don't trust your airlock. I'd keep the temp where it is and just wait impatiently.

Wheats, especially Belgians, have a very persistent krausen. My last one lasted like 3 weeks. I finally sanitized the handle of my spoon and reached in to disturb it. If fell down and settled to the bottom in a day after that.

I figured that it would take a while for this thing to ferment out, but the persistant kreusen was a bit of a suprise.

I was hoping to have this beer done by Thanksgiving, but at this point, it is looking more like christmas.

Also, the sulfur smell will disappear over time, it is a result of the yeast, don't worry about it. When I did my first Belgian I thought I had a bad batch, but after a month in the bottles, it mellowed nicely.