So, my dad is considering building some contraption out of PVC pipe and Brita water filters.
Now, I've read the side of the box on those things and they say nothing about filtering down to x number of microns. They do claim to remove certain metals and chemicals, IIRC.
While they make mediocre city tap water taste a lot better, I have no evidence to believe that they would make the water safe if it's not already reasonably safe.

Assuming that he still pre-filters for sand and large grit before the water pitcher filters, is he wasting his time thinking that these filters will get out all the smaller, nastier things?