Portland Water; Chlorine and Chloramination

From the Portland Water District: “This facility began treating water in February 1994 using ozone. Ozone is a powerful disinfectant that kills potentially harmful microorganisms and is 99.99% effective against viruses and Giardia. Treatment includes screening, ozonation, UV light treatment, chloramination, and corrosion control. Also as a result of a citizen referendum, fluoride is added to the water at the plant to promote dental health.”

So, the difference between chlorination (Cl) and chloramination (Cl-Am – my shorthand), is that Cl will dissipate from water left overnight on the counter, and that Cl-Am will not. At the levels used for disinfection of public water, the Cl-Am is not dangerous to humans, but apparently will kill fish in your aquarium. How comforting. Best way to remove it if you want: a water filter. Which then go into landfills. sigh.