Here in Appalachia, one has to be cautious of their water sources. Coal mining, before it was well regulated, released several toxins and heavy metals from within the earth, out into the water ways. Most streams and rivers in my area contain certain amounts of lead, mercury, arsenic, cadmium, selenium, and hexavalent chromium, even 40 years later.

Both natural springs, and rain are plentiful here in KY, so finding treatable water isn't a problem. One just has be be aware of their water source.

In response to your question: It is your project so do what you think is best. I do believe an addition or two could benefit others, if you are up to it, though. Chemical contamination is a widespread phenomenon in North America. Your prerogative, Bro.