Pond Boss Forums GENERAL QUESTIONS Help Oily film on pond surface - 7/07 - Photos added!!

Hello to all! This is my first post and I sure hope I posted it in the right place.

Before I ask your collective advice, let me describe my pond: It's small, only about a quarter acre in size. It has an average depth of 6 feet. It has a raised bank all the way around it, so it does NOT collect any runoff. It only gets what falls straight down out of the sky. If the water level gets too high it goes out through an overflow pipe. The pond was dug in 1989. I have bass and bluegill in it - probably too many of each!

Okay - here's the problem: Every year I do battle with an oily film that develops on my pond. It's like somebody dumped a bottle of cooking oil or a very light viscosity motor oil on the surface. If the wind is blowing a little, it only covers about one third of the surface, as the wind pushes it to one side of the pond. When the wind blows really hard you'll find me at the end where the oil collects sucking it off the surface with a Shop Vac. The only time I'm able to put a dent into it is in late spring when the fuzzies from the local cottonwoods fall in the pond and sop up the oil...as the fuzzies collect on the side I rake them out and then I'm good for a few weeks before the cycle repeats.

This film does not seem detrimental to the fish and plants or any other wildlife...whatever this film is it did not originate on the Exxon Valdez! But it coats anything that floats in the pond (including me on my blow-up raft!!) with a sort of greasy film that's basically...sort of icky.

Where is it coming from and how do I make it stop?

Thanks in advance for any and all help!