Boy, am I glad I found y'all! I bought a 30 yr old house with a water well. It has a motor driven air pump that blows air down the well. Water comes up and empties into an above ground concrete tank, about 1000 gallons. There's a typical well pump mounted on a pedistal next to it with its intake plumbed down into the cistern and its output into a typical big blue tank that runs into the house. I can't find any filtering device, save for one under the kitchen sink. I'm about 75 miles north of the gulf coast, 225 ft in elevation, and far enough from Houston that the air's not chunky. I've never seen anything like this setup before, but I'm a city boy and therefore, a throughly dangerous man (a little bit of knowledge...) What's the best approach to a proper filtering system? Is this a safe/practical setup? The pump is less than a year old. The cistern is not sealed airtight. What do I need to do for control of bacteria? I'm an HVAC guy in new home construction so I know which way to turn a wrench, but I'm way outta my element here and defer to more educated folks for direction. Any help is greatly appreciated.