we use eparcyl and we also have OE42 from oasis - the smell is not overpowering and wouldn't call it a sulphur smell like rotten eggs - it's just you can smell it just slightly in the air in the morning at that end of house and near the tank openings although they are obviously covered with the...
i didn't explain very well but there are two tall pipes an inlet air breather and an outlet breather pipe both above roof level one to and the other from septic tank - both pipes have caps on them due birds etc and we heard that you could get carbon filter caps which obviously help get rid of...