Process:  -Water comes through a filter -The filter has small pores to catch pollutants -The filter will catch chlorine, heavy metals, and other chemicals -The filter allows water and mineral ions like fluoride to pass through -The water on the other side of the filter is much cleaner -
 Question: What is the effect of the water is contaminated prior to filtering through outside interference. on only already purified water is run through the filter.?
against