Materials
10 nutrient agar plates
3 sterile 1L bottles
Membrane filter system
Alcohol and Tweezer
Bunsen burner
Method
First, I labeled the 10 agar plates by one negative control, 3 reverse osmosis, 3 fountain drinking water at kishwaukee, and 3 tape water of friend’s house. Filter holders were sterilized for 3 minutes. Fixed the membrane filter and 250ml sample water is placed into upper beaker and applied vacuum pressure, which helped water pass through the membrane filter in the lower beaker. The filter membrane is removed from the holder with sterile tweezer and placed on