Abstract: The invention is directed to a process and a medium for simultaneous determination of the number and presence of living fecal coliform and Escherichia coli in a sample comprising 6-O-alpha-D-galactopyranosyl-D-glucose or isopropyl-beta-D-thiogalactoside as a galactosidase inducer and methyl-beta-D-glucuronide as a glucuronidase inducer. The sterile semi-solid medium also comprises non-target bacterial inhibitors, target bacterial enhancers, and multiple fluorogen and/or chromogan substrates that produce color and fluorescence upon cleavage by a specific enzyme expressed by the target bacteria in which expression is enhanced. The simultaneous detection of total coliforms via its expression of beta-galactosidase, and Escherichia coli as the target bacteria via its expression of beta-galactosidase and beta-glucuronidase is achieved rapidly and efficiently using this medium.