I use a small amount daily in my vap.....the bags get pretty yucky (especially when I was running low and would re-ingest the vap in and out of the bag 'till it was gone - works well by the way) but I just get oven bags as GN suggest...I clean the valves and stuff in grain alcohol and it cleans up nice....so I may end up spending about $10 a year keeping everything like new. I am using the Herbalaire and find it worth every penny herbalaire vaporizer