By Aaron B
The purpose of this experiment was to find and compare the amounts of bacteria from different water sources (home-filtered,city tap and commercially bottled). The sterile disks that were used for collection were soaked in each of the different water sources and then placed in zip lock bags on-site. This process was carried out using a pair of sterilized tweezers which which were the only objects that came in contact with the disks. Afterwards, the disks were transferred to petri dishes. The dishes were then incubated for a forty-eight hour period.
After completing the experiment it was found that the home filtered, city tap water contained, the most bacteria. It had twelve colonies in three dishes. The cleanest samples were the ones collected from the bottled Poland Spring water, which contained four colonies over three dishes. One of the cleaner samples was the one from School X, which contained five bacterial colonies over three dishes. The Sample from Temple university, fell right in the middle with six colonies over three dishes.
The purest form of water among the sources tested, was bottled Poland Spring Water. This project would have been easier to complete if it were possible to take the the Petri dishes to the locations. That would have meant less chance of accidental contamination from ether air or the zip lock bags employed for transport.