For detection of presence and absence of coliform bacteria in water. Kit contains sterile bottle Principle There is a need for rapid methods to quickly determine the indicator bacteria and pathogens in water. Monitoring microbiological quality of drinking water relies on examination for indicator bacteria such as coliforms by using PA E. coli kit. It contains all the essential nutrients for the growth of coliforms, including Escherichia coli. Presence of Escherichia coli and coliforms is indicated by colour change of broth to yellow from initial purple colour. No colour change of broth indicates absence of coliforms.