"Sean R. Kerns" wrote:
The other thing I noticed a little while ago was that the "oil" seems to
disappear at night, which makes me wonder if it's even oil at all. Is it
possible it's just some kind of algae haze?

I saw a PBS show years ago, where they demonstrated oil's ability to thin
out to just a few molecules thick. They took a teaspoon of cooking oil and
placed it on a park-sized pond. A time elapsed camera showed the oil
spreading over the entire pond.
BV.

And that's how they kill mosquito larva in ponds. ;o) Only works on a calm
day though. ~ jan

See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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