A science demonstration for Troy's water
Basically fill an aquarium with water that represents the typical amount of water consumed by Troy during a given period of time. Then, add dyes in a ppm that is the same as the ppm of certain toxins.
In particular, where the amount exceeds the "safe level", add that amount first, then the amount in excess.
2017 drinking water quality report: http://www.troyny.gov/wp-content/uploads/2018/04/AWQR17.pdf