Drive the RV to a certified dumping station, found at campgrounds or rest areas on highways. Put on your rubber gloves, mask and safety goggles to prevent contamination.
Open the back panel on the righthand side of the RV where the black water tank is housed along with the nozzle and dumping hose. Attach the dumping station hose to the black water tank dumping hose and turn the dumping station pump on. Allow the tank to drain.
Go inside the RV and pour five capfuls of chlorine bleach into the toilet and flush. The bleach kills bacteria and reduces odors in the now-empty black water tank.
After a week of light use (less than one flush a day), pour one cup of water softener into the toilet and flush. This chemical keeps the water in the black water tank from going fetid and prolongs the life of the tank and hose.
