I have Raritan electric toilets, original equipment and they use salt water. They need to be rebuilt I think because especially the aft head dosent go down well. I have some kits to replace seals etc. Anyway, they both stink up the bilges, especially the forward head. I wonder if the vent is somehow not properly venting to the outside and venting into the bilge. When the holding tanks reach about half full and we close up the boat it stinks in the boat sometimes as well. We have tried every kind of tank additive and some work better than others but the heads still stink and the more full they get the more they stink. Someone said to change them to run on fresh water, but I doubt that will really cure this problem. Anyone else have this problem? Or a possible solution? Hopefully without throwing a whole lot more money away.