Colitag is a pre-dispensed, dry blended reagent formulation containing salts, nitrogen and carbon sources and specific indicator/nutrients for rapid confirmation of total coliforms and E.coli. Positive samples are detected by a visible colour change.

Simply fill a sterile tube to the level, mix and then incubate at 35 °C. The formation of a yellow colour in 24 hours or less indicates the presence of total coliforms. Positive tubes are then checked for the presence of E.coli by looking for fluorescence under UV light.