I am planning to test types of simple filters (like gravel, sand, cotton balls, coffee filters, charcoal). My water source will be a sample of my local creek water.
I'm curious about if you were out in the wild and you only had simple materials to filter water with, what would you use?
I researched a way to test turbidity, but I don't know where to get the materials I need (reagent? if doing visual test). Also I want to test for either nitrate or metals.
Can you give me some advise. My project is due on Feb. 14, 07.

