Hi guys , My pond is almost finished now and starting to fill .The only problem is not much rain. When it doesn't rain for a week or so the pond gets a brown film on the top of the water. It almost looks like oil without the colors that oil causes. Its just a rusty color stain that floats on the top of the water in patches.The water is also very muddy . When it rains the stain disappear and come back in a week or two. The pond has a couple of trees that were left in the pond for cover. I was wondering if these trees could be releasing some type of stain that could be doing this. Any thoughts would be appreciated. Thanks , Dave