Sat at the dock and had my coffee this morning. There was some sort of film on the water. Didnt cover the whole pond, was pushed to one end of the pond by the dock. There were bubbles in it, with a brownish color to it. Was wondering what causes that. I took a pool test strip and tested the water. PH 6.4, Alkalinity 0, hardness 100. Not sure what that all means, but it didn't look good. Any thoughts?