Be careful of bleach water in the RV. Ask me how I know
In the summer when the RV isn't being used, we put cooking oil in the toilet (don't flush). The oil will not evaporate as water does and it keeps the rubber seal in good shape.....otherwise the water evaporates and the seal gets hard and brittle.
One can also put some Dawn detergent in the black tank and it helps with grease build up and odor. We normally use the recommended 'orange' septic tank liquid (flushed in through toilet) . This is done after each time the black water is dumped.
Good luck, enjoy your RV. Books and experienced RVers are your best source of knowledge.....and, of course, your own lessons learned, etc.