Testing for bacteria in water

The H2S vial test is one of the easiest way to check for the presence of bacteria in drinking water. A simple glass vial containing a small coated paper is all that is required. Fill the water it needs to be checked till the fill line. Observe for 24-36 hours. If the water stays brown like in the bottle of the well, the water has no e.coli and is good to drink. If it turns black like in the bottle on the right then it has bacteria and cannot be drunk directly. Boiling the water may be a good way or using a water filter which removes bacteria.