Seewald Laboratories is the first laboratory in EPA Region III to be fully accredited for Fecal Coliform analysis by Colilert18/Quanti-Tray in Non-Potable Water.

IDEXX Quanti-Tray/2000® Technology at Seewald Laboratories, Inc.

There are many benefits in using the IDEXX Quanti-Tray/2000® and Colilert-18® system. The Quanti-Tray/2000® method requires less equipment and no media preparation allowing us to be cost effective. The technology also enables greater efficiency and accuracy as many samples can be run in a short amount of time while producing results over a wider and more specific range. Clients can also experience the benefits as accurate results can be determined in 18-22 hours and the method can detect from 1 to 2,419 colony forming units per 100 mL of sample.  However, results can exceed this upper limit by using a dilution, if deemed necessary, as the sample may exhibit excess particulates.

Fecal ColiformThe technology involves Colilert-18® substrate being added to a sample, which causes a yellow color reaction and/or fluorescence after proper incubation if coliform bacteria are present. The IDEXX Quanti-Tray/2000® system uses a 97-well tray, that when put through the Quanti-Tray® sealer, evenly distributes the sample across 49 large and 48 small wells. This allows for the quantification of total coliforms and E. coli or fecal coliforms in a 100 mL of sample. MPN determination is made by counting the large and small wells that have turned yellow and then the result is extrapolated from the Quanti-Tray/2000/200 MPN Table®. The positive yellow wells that fluoresce under UV light can also be counted for E. coli determinations. Both drinking and non-potable waters can be analyzed using the IDEXX Quanti-Tray/2000® and Colilert-18® system.

Click here to view the approval letter from the United States Environmental Protection Agency.