[Dave W]

Usually one of the deodorants will keep the odor down. Since we seasonal, I simply do a good back flush and cleanout every other dump which suffices. We generally take a lengthy trip each fall. On the last leg to home, I will add a few ounces of easily found Rid-X which has both same basic ingredients as Happy Camper at a lot less dollars(look at the SDS). Remember, these are holding tanks, not septic tanks. All you want to do is to better break up whatever is in there to do a full dump. Rid-x and Happy Camper will do that job. That blue stuff in a plastic bottle is for all intent, a deodorant