Plot twist: The next companion is a normal girl/boy who only dies once in their lifetime and has no remarkable back story but he thinks they’re wonderful because they are human and the Doctor needs reminding that you don’t need to be a mystery to be remarkable.
so basically we want Donna back
Just a pool, disguised as a pond, with a trampoline instead of a diving board.
I wrote a paper about these kinds of pools several years ago for a class when they were just prototypes. These pools have a natural filtration system that run based on the plants that are in the pool that give the water nutrients that allow it to not only be crystal clear, but you are also able to drink the water because it becomes so clean. And the best part is that once the initial filtration system is installed and calibrated, it maintains itself and eliminates the need for chlorine or constant maintenance like salt water pools.