I had this problem with a client's pond this summer on several occasions. It was just stocked with fathead minnows and low concentration of bluegills. I think it was just due to some algae growth. We have an enzyme that is often used for getting rid of smells that did the trick. Any other solutions? I'm guessing that most people don't have a problem, but we all have some clients that are a little more sensitive to things to put it nicely.
robert B