The first picture is of a non-treated water sample from the Mara River. The approximate coliform counts for this tray were as follows; Purple - 4, Blue - 140, Pink - 140.
The second picture is of the exact same sample from the Mara River after it has been treated by the Steripen. The approximate coliform counts for this tray were as follows: Purple - 0, Blue - 1, Pink - 15.
(I know the pictures are a bit blurry but I had to take it with my cellphone at a hotel in Nairobi.)
Each different color represents a different kind of bacteria with Purple being E. coli. As you can see, the Steripen killed most of the bacteria in the water.
The instructions for the Steripen do say that you are not supposed to try to sterilize water that has a large amount of particles in it because the light can't reach all the water. The water we tested was pretty murky...that is why I believe it didn't kill all the bacteria in the water for our little test.
Here is a picture of where this sample of water came from. You can see Amanda on the bank of the river taking the sample.
Here is a nice picture of a standoff between a large Nile Crocodile and an Elephant...this was just on the other bank of the river. The Elephant was trying to get down to the water but the Croc wouldn't let him pass.