Two things to keep in mind. If you're new to Permanent camping, and I expect that you know this. You shouldn't emty the black water tank until it is at least 2/3 -3/4 full. The reason is that if you drain it before it has a good volume of water in it, the solids may stay behind. BAD. As for the black tank flusher, I have one. Bought it at local RV dealer. Hook it to a garden hose, string the hose through the door and into the "thinking room". Hold the ball, or flap open, stick the flusher down inside, it squirts water sideways. Turn it round and round so as to blast at all sides of your tank. That should clean it right up.