A Comparison of IDEXX Coliform and E. coli Tests

The Strengths of IDEXX's Coliform and E. coli Tests

Colilert® Lowest cost and most popular Defined Substrate Technology® (DST®) test
Colilert®-18 Ideal for afternoon and rush samples as well as real estate, new well and new construction samples
Colisure® Obvious endpoint color Longest read window (24-48 hours)
Beginning the week of March 19, 2007, all IDEXX Colilert® and Colisure® products will be irradiated. View Frequently Asked Questions on the new process.

A Comparison of IDEXX's Coliform and E. coli Tests
IDEXX's family of coliform and E. coli tests offer you the flexibility of U.S. Environmental Protection Agency (EPA)-approved tests that give you results in 18, 24 or 48 hours. You can also choose between a yellow or magenta positive endpoint. The chart below outlines the features of each of these tests.

Feature	Colilert	Colilert-18	Colisure
Time to Result	24 hours	18 hours	24 hours
Incubation Time	24–28 hours	18–22 hours	48 hours
Quantification Options	and MPN tubes	and MPN tubes	and MPN tubes
Shelf Life	Up to 12 months at 4–30°C	Up to 15 months at 2–25°C	Up to 12 months at 2–25°C
Formats	10 mL predispensed, 100 mL, 250 mL	100 mL	100 mL
Prewarming	No prewarming required	Prewarm P/A samples to 35°C	Prewarm P/A samples to room temperature
Coliform Signal	ONPG turns yellow	ONPG turns yellow	CPRG turns from yellow to magenta
E. coli Signal	MUG turns fluorescent	MUG turns fluorescent	MUG turns fluorescent

For best results, use IDEXX Antifoam with Colilert-18 and Colisure when using Quanti-Tray.