Colitag™ is a 16-48 hour water test (P/A and MPN) that detects as few as 1 MPN of E. coli and other coliform bacteria in 100mL of water. Colitag™ is US EPA approved for use as a presence absence test and in the Most Probable Number (MPN) format as specified in Standard Method 9221 for compliance monitoring of total coliforms and E. coli in drinking water.