You Are in Charge of Water Quality for Your City's

Multiple Choice

You are in charge of water quality for your city's water treatment plant. Of the methods at your disposal, which will be the most efficient and cheapest method of determining the number of viable bacteria in the water coming out of your plant?

A) Direct counts using a microscope and a counting chamber.
B) Using a Coulter counter machine.
C) Performing serial dilutions and doing spread plate counts.
D) Using membrane filtration followed by placing the membrane in a growth medium for colony counts after incubation.
E) Biochemical analysis of secondary metabolites in the water that are given off by bacteria.