It would appear that, at least temporarily, Ive solved the sulfur smell issue created by some batches of fermenting apfelwein. This is a workable solution for those who are fermenting in a living space or an apartment.I made a batch of apfelwein following Edworts recipe EXCEPT I used Cote des Blanc yeast (because that is what I had on hand) & yeast nutrient at the recommended rate (since some said this would reduce sulfur smell). The fermenting carboy is on a counter in our dining room due to lagering temps in the garage. I awoke to *very strong sulfur smell permeating the entire main floor of our house today (so much for the yeast nutrient argument). Obviously I realized this setup wasnt going to work, especially in the dining room. SO I made a filter housing out of household materials ($0) to attach to the top the fermentation lock. I filled the filter housing with activated carbon ($6 from wallyworld) and . INSTANT SUCCESS! There iscoming from the escaping gas out of the filter atop the fermentation lock. I aired out the house and the filter has kept the smell to absolute zero for several hours now.Heres a link to how I did it (the photos have notes so mouse-over to see them.)I expect that at some point the carbon in the filter will become saturated and need to be replaced to continue absorbing sulfur. There is enough carbon in the single container I purchased for dozens of filtrations. Ill keep you posted on how long it works. This is my first batch of apfelwein so Im not sure how long the sulfur smell persists during fermentation anyone know?(KEYWORDS: smell, odor, gas, sulfur, sulphur, sulfer, sulpher, filter, how to, DIY, make)