Sounds like it's staying way to wet. I'm thinking anaerobic break down of the potting mix, which means there is no air getting in & it's putrifying. They don't have to stay soaking wet. Let the top inch or so dry some between watering. Most bog plants live a couple inches above the water line on hummocks, most of the season with periodic inundations.
Hope this helps.
Frank

Yeah a bad smell is a sign that things are far too wet. Try lightening up on the water instead of adding charcol.

ok that helps alot actually, so should i repot it and add MORE pumice or if i ease up on the watering will the smell go away or both lol