Anyone have any idea how to stop colostomy bag stench?

This is the colostomy bag I use(a href="http://i.imgur.com/vTHkY.jpg)," rel="nofollow"http://i.imgur.com/vTHkY.jpg),/a everything is going fine at the moment, everything except the smell. I appreciate that I'm carrying around a bag of **** but the smell shouldn't be this bad and I've never known anyone with this problem. When I've had the bag on for more than a day, the smell will break through the bag and stink the joint right up. I was told to use the bag in my picture because it has a "filter" on it, but that does absolutely nothing, the nurses said it should filter out the smell and let the gas ease its way out, so far it has done neither of these things. Does anyone have any advice on a type of bag that helps with the smell or any type of product I could use? Any help would be greatly appreciated, cheers guize.