Coliquant EZ Gel is a petri dish test used to detect E. coli and coliform bacteria in water samples. Water samples are collected in clean, cold bottles and poured onto a growth medium in the petri dish back at the lab. The medium feeds the bacteria, allowing them to multiply and form visible colonies during incubation. The number and color of colonies indicate the presence and levels of coliform and E. coli bacteria, with deep purple colonies specifically identifying E. coli.

1. Coliquant EZ Gel
What it is
How to do it
What it tells you

2. What it is
Petri Dish culture test
For E coli and Coliform Bacteria

3. Indicator Species
Feces come from animals
Feces can’t be detected (spread out)
Certain bacteria are found
exclusively with feces= indicator
bacteria

4. Bacteria
How do bacteria reproduce?
Asexually
Clusters of bacteria therefore form,
known as colonies
Colonies can be counted (bacteria
too small alone)

5. Field Sampling
A small bottle of water is filled
Extra care is taken to:
Keep the sample bottle clean
Keep the sample bottle cold
The small bottle then gets poured
onto petri dish back at lab

6. Incubation
A measured amount of water sample
is then poured onto a medium
The medium feeds the bacteria.
This is called “culturing” bacteria
With food and warmth they multiply
and form colonies

7. Analysis
Colonies/100 mL
Color of colony indicates if it’s a
strain of coliform and e coli

8. Colors
Pink= not E coli
Deep purple=
Teal= not E coli E coli