Poor Little Fish by Yan Lu is an unusual approach to saving water. When using this basin, users are prompted into thinking about consumption when the water level in the fishbowl goes down (but does not actually drain out). There are two separate pipelines, so the water level will go back to where it was once the water stops running. As well, the water from the tap is pure, as its pipeline does not connect to the bowl.
Watch how it works here:
a magyar állatvédelmi törvény szigorúan bünteti az ilyen formájú akváriumot.