How to Assess a Pond

First you observe. You see if there are any dead plant or animals. Then for algae blooms or a film or foamy surface of the water. Then you examine the algae and insects under a microscope. You then identify it is good algae, or bad. Then you test the water quality. You can test temperature, nitrate, nitrite, ammonia, or pH. After that you do chemical testing. You can test for mercury, foam, chlorine, soap, oil, or gas.