I have noticed a brown sludge on top of the pond. It just started recently with the cooler weather. Got rid of it the first time four days ago by flushing with new water and God's little rain shower. Now its back.. It seems to be water based, rinses of my hands pretty easily, oily sheen, and iridescent. Appreciate any information on this one!

Dead zooplankton?

Could be just about anything or dead zooplankton as Chris says. I too see it this time of year, but I've also seen it other times of year. I wouldn't worry about it. It won't last long either. I do see it more in fed ponds vs. not.

Are you adding well water? I see it more frequently if I am adding ground water.

I was thinking that it was dead zooplankton, but i was wanting to make sure (double check). Haven't used well water in the last few days on this pond.

Thanks Cecil and Chris.

Out of curiosity, is your pond relatively deep (max-depth > 10')?