IDEXX - Colilert - For Detecting Total Coliform and E. coli
Colilert, which simultaneously detects coliforms and E. coli, is a global leader in coliform and E. coli tests, with dozens of regulatory approvals worldwide. Samples turn yellow when coliforms are present and also fluoresce to indicate the presence of E. coli. Colilert can be used for presence/absence testing or quantification using Quanti-Tray*, Quanti-Tray*/2000 or multiple-tube MPN methods.
- The Colilert test simultaneously detects or quantifies both total coliforms and Escherichia coli, with results in 24 hours.
- U.S. EPA approved and included in Standard Methods for Examination of Water and Wastewater.
Product Information
Equipment & Accessories
Quanti-Tray/2000 (WQT-2K)
120 mL Shrink-Banded Vessels with Sodium Thiosulfate (WV120SBST-200)
SealerPlus (WQTSPLUS)
6-Watt Fluorescent UV Lamp (WEA160F)
UV Viewing Cabinet (WCM10)
Procedure (Presence/Absence)
Step 1
Add reagent to sample and incubate at 35°C ± 0.5°C for 24 hours.
Step 2
Read results:
Colorless = negative
Yellow = total coliforms
Yellow/fluorescent = E. coli
Procedure (Quantification)
Step 1
Add reagent to sample.
Step 3
Seal in Quanti-Tray Sealer and place in 35°C ± 0.5°C incubator for 24 hours (in other countries, the temperature requirement may be different per regulatory requirements).
Step 4: QuantiTray/2000
Quanti-Tray/2000—Read results:
- Yellow wells = total coliforms
- Yellow/fluorescent wells = E. coli
- Count positive wells and refer to MPN table
