Reverse osmosis is the only kind of "filtration" that truly cleans your water. The pores are so small that O2 and CO2 and alcohol cannot get through, only water molecules and the very few things smaller than water molecules. Other filters get some things and not other things.

We evolved to detect most kinds of naturally-occuring dangerous foul water at very low levels. I should have listened and not kept drinking it. Anyhow, I didn't get too sick.