Peggy, Your book is great, I even enjoyed reading about waste systems - thank you! I used KO in my tank but with no significant results. I believe the problem is insufficient air venting in the tank. I then tried Ordorlos and it seems to be doing well. Is there a compatability in the chemicals if I use CP in the toilet and Ordorlos in the tank? I do not want to diminish my results, but I would like to use both on a regular basis if that is ok. Rob