Food&Water Q.C.


CHROMagar™ Liquid ECC

Click on the picture for
Packaging / Colonies appearance

For the simultaneous detection and enumeration of E. coli and other coliforms
in water samples.

Broth Technique Product

Typical Appearance of microrganisms

E. coli → blue
Other faecal coliform bacteria → purple
Other gram negative bacteria → colourless or inhibited

Order References 

Please use these references when
contacting your local distributor:

5000 mL .......... EL382
To download the certificate of analysis, please indicate your lot number below :


Medium Performance

  1. Simplicity: Very easy to prepare compared to agar based culture media.

  2. Broth technique: Innovative chromogenic culture medium to be used in broth form (without agar) within the water filtration technique, to impregnate the pad or the filter. You can take an aliquot so to prepare the exact quantity of broth you desire. Thanks to this flexibility, you get rid of the prepared media stock and shelf life management headaches and get the insurance to always work with fresh media.

  3. Economic: Only 2 mL/test (instead of the 10-20 mL for other culture media).

  4. Easy Method: CHROMagarTM Liquid ECC allows a simultaneous detection and differentiation between E. coli and coliforms in one medium. This is helpful to determine if there is organic contamination (coliforms) or faecal contamination (E. coli). The use of this technique involves less work in comparison with traditional methods (MI Agar).

  5. Easy to read thanks to the high colour contrast between colonies. There is no mixing of both colours (contrary to other chromogenic media on the market). Colonies are either blue or purple.

Medium Description

-Standard Analytical method for Water Quality Samples at Hong Kong Environmental Protection Department.

Gain flexibility using powder rather than ready to use plates: Use the entire pack, or just a portion if there is a need for a smaller number of plates,. If kept under appropriate storage temperature, CHROMagarTM Liquid ECC has a 4 years long shelf of life. This flexibility is essential to avoid the waste resulting from expired-unused plates.

Please refer to our IFU and Material Safety data sheet for complete information about the medium. 
CHROMagarTM is a trademark created by Dr Alain Rambach.
All pictures of our products are CHROMagar property and should not be used without our acceptance.
Last update: 23-Nov-2018

Focus on E. coli and coliforms

Different regulations exist for E. coli/Coliform research in water samples. This can be explained by the importance of these germs in determining water and food safety.
Worldwide, water and food quality control for human consumption are based on detecting the presence/absence of E. coli and coliforms.
Coliforms, Enterobacteriacae able to ferment lactose (lactose positive Enterobacteriacae), are bacteria present in human and warm-blooded animal intestinal flora, in the soil and water. Coliforms are proof of organic, environmental or faecal contamination. Faecal contamination, due to colifoms coming from animal waste, consists mainly of Escherichia coli and thermotolerant Klebsiella.

E. coli and Coliforms Epidemiologic Issues

E. coli can contaminate drinking water when the water treatment system is inadequate or during periods of very high rainfalls.
Monitoring of food and water production is essential. High contamination may lead to suspension of the water supply and food recall by supermarkets.
In the U.S.A. the EPA recommendations through the Total Coliform Rule (TRC) are:
- <100 CFU/100 mL for a body-contact recreation water quality.
- <1000 CFU/100 mL for a fishing and boating water quality.
- <1 CFU/100 mL for a drinking water quality.


Detection and occurrence of indicator organisms and pathogens


Katherine H.Baker. Water Environment research, vol70, No.4 (Jun 1998), pp405-418 (Extract)

Enumeration of E. coli in environmental waters and wastewater using a chromogenic medium


HO B. S. W,TAM T.-Y. Environmental Microbiology Section, Waste Policy and Services Group, Environmental Protection Dept, Hong Kong Government, HONG-KONG

A Comparative Study of Selective Media Used to Detect and Confirm Coliforms and Escherichia coli in Water Samples Using Membrane Filtration.


1995. Abstract by Collyer J.
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