Started reading this and see early entries about aerating water.
If I needed to, I do this.
It is multi-purpose - aerate water, stir laundry, make compost tea, wash soil to separate
clay and sand, . . . nobody at the laundry thread watched this. I am disappointed.
Only one moving part.
Only one hand needed.
No batteries required.
Just give it a few punps whenever you pass by.