chainegang wrote:
As someone who has used non potable water for drinking and cooking purposes while away from safe sources, I have on many occasions filled my 30 gallon on board tank with clear river water of water stated as non potable or unsafe to drink, and treated with a ratio of 2 onces of household bleach. Some times the bleach taste comes through as too much was put in. I have also used granulated Spa chlorine not swimming pool chlorine as the Spa chlorine is more convient. One teaspoon to 15 gallons of water. Spa chlorine has a higher percentage of chlorine and has little in the way of non disolvable matter. In both cases the chlorine is mixed with water before pouring into the holding tank. I would submit to you that this procedure would take care of growth of unwanted substances when applied to longer term storage.
Problem is crypto and giardia are relatively immune to chlorine.