I think you have misunderstood the my reasoning behind secondary disinfection (pathogen only); it is usually used as there are other vectors of contamination such as the following:



- contaminated secondary holding surfaces that are not disinfected that come in contact with the treated water i.e. the second container you have, if it is not cleaned and sanitized prior to being used may have pathogens on the surface that can multiply if given the right conditions



- contamination through introducing untreated water to stored treated water (spills, leaks)



These are even bigger issues if you are going to let the water sit in the secondary storage for any length of time, not a big issue if the water is going to be consumed right after treatment.

