I agree that water softners will do nothing to keep the odor off. IF you really want the odor to go away is to use the proper stuff. Happy Camper makes an enzyme that breaks down the solids and turns it back into water. Enzymes eat up the waste and keep the tank clean. Some folks just do not want to spend the money on something that was made strictly for that purpose. Lots of water does not solve the problem either. It will not break down solids.