Do you have any information on where to send the samples? I've taken samples before when I was an enforcement officer and there's a very strict procedure as to how it's collected. It must also be collected in a sealed and certified container, and labled with the chain of possession.
We have black algae in our water system but the city says there is no harm in it and they don't test for it. With Melanie's weak immune system, we didn't drink it. Only bathe, boil and cook, and bathroom.