Self Cleaning Betta Aquarium - Simply pour fresh water in, and dirty water is expelled through a tube and out of the tank while your fish swims happily within. There are no filters, batteries, or cords.
Portable RV Fresh Water Tank Lets You Dry Camp Longer
Punch a hole in the top of a bottle of vinegar and sit the bottle in your toilet tank. In doing this you will save water, as the tank wont fill as much, the vinegar will clean your toilet AND tank on each flush, it leaves the bathroom smelling fresh and it doesn't harm any component of your toilet OR the environment when flushed.