Dump black ,hook up with dedicated hose to tank flush nozzle run for about 5 minutes ,dump again. close black tank valve . Let flush nozzle run for a few minutes to wet black tank. While I am doing this I dump grey tank.Drain dump hose disconnect flush nozzle from black tank. Rinse drain hose with a little fresh water, drain disconnect store in sewer compartment. Fresh water system has its own separate compartment no cross contamination. After trip and we are packing down Rv I will hook up and flush tanks again at home. Just trying to keep solids build up out of tanks. I always store tanks wet when done with chemical in grey and black. I guess I am anal about some things. When we first bought RV (used) we had odor problems. And yes I live in the city! LOL!
