We have to drink bottled water at home. Our water has tested positive for bacteria several times. We found this out when the entire family kept suffering from a stomach virus of some sorts... over and over again.
The company that tested our water quoted a price to install a light, but I would like to do this myself for the experience. First off, can a light be purchased online and what kind of maintenance does one require? What prices are we looking at?
You might be talking about altra-violet light, where water passes though this light before it get to drinking glass, I installed one awhile back, under kitchen sink type, not sure the cost but use the key words in google and see what comes up.
Fix it right the first time, so you won't have to fix it a 2nd time.
Around here, Home Depot and Lowe's sell UV systems right in the store. Of course, private wells are popular in my area. The UV lights run around 800 bucks for a 13 gpm whole house system. They are standard fare in my neck of the woods.