I have had good luck with ODORLOS. I use the amount for a 40 gal tank upon charging. Only once or twice did we have an odor problem. Then, according to directions, we added more ODORLOS as we could not dump right then. The reason we use ODORLOS is that we are both chemically sensitive. Even though we have to use more of the product to achieve the desired results, we can breath and not have asthma attacks that have been initiated just smelling the other stuff. And, it will not wreck your seals. It has a lubricant in it. This product does not cover up smells with perfume. It breaks down the waste. I am not in any way connected with the company. I'm just glad there is a product out there for someone with my problems. We bought the TM because it is constructed without formaldehyde and other nasty toxins, so we certainly don't want to contaminate our new home away from home with those things! :P